The new iMacs sport an enclosure and display panels (20in 1680×1050 and 24in 1920×1200) which look on the surface, as well as on paper, identical to the previous generation but according to some of our oldest and most reliable sources at the highest levels within Cupertino’s Mac Hardware engineering division.

There is a lot more going on here than meets the eye in this latest update, even if you dig deep into Apple’s published specs so far.

The enclosure is now “internally ribbed” in key locations and has reinforced hardware at the “foot hinge” to improve the smoothness and ease of adjustment (while preventing “sag” or unintended movement from happening too easily) of the iMac’s one moving part.

There are also a number of tweaks to the cooling system, the placement of internal components over the last generation, and a change in materials for several small parts — one source suggested that all of the screws which hold the iMac together are now made of a different alloy which is “greener” from start to finish and is more easily recycled.

This is apparently part of Apple’s top to bottom “Green-ing” efforts and attempts to make its machines among the easiest and most completely recyclable in the world.

As for the display panels, set a new 2008 iMac down next to its 2007 counterpart, or previous generations of “whiteout” iMacs that preceded the current “black on brushed aluminum” model.

You’ll see a clear difference in display quality, according to our highly placed source and more than one other in the Asian manufacturing sector among Apple’s supply partners in China, most notably.

The truth however is less dramatic. Apple is working on differentiating its hardware lineup by including discrete coprocessors for tasks such as video encoding, graphics design acceleration, and other high performance applications.

This sort of acceleration has been possible for a while now with the OS X Acceleration Framework, which takes advantage of whatever hardware is available on a machine, like SSE or Altivec instructions, graphics processors such as the Intel GMA or Nvidia chips, and now dedicated coprocessors.

Sporting powerful “Penryn” 45-nanometer mobile Core 2 Duo processors from 2.1 to 2.6GHz, these new laptops are poised to crush the competition and expand Apple’s market share considerably. Read on for specs, analysis and more details!

Both the Macbooks and MBP’s have received significant enclosure/industrial design tweaks — notably, both sport the same “modern raised-button” keyboard design as the Macbook Air and Apple’s latest stand-alone ‘board.

Most of the new laptops are build around the “standard” Penryn chip, running at 2.1-2.4GHz with 3MB of enhanced on-chip cache memory; as Rumors reported previously in this article about Penryn & future Macbook Air specs, this new cache is faster and more intelligent than previous Merom/Santa Rosa based designs which included 4MB of cache.

Although 25% less cache memory size may seem like a downside, this is actually part of what makes these new 45nm Penryn chips so remarkably efficient.

Higher-end Macbook Pro models at 2.5 and 2.6GHz sport 6MB of this highly optimized cache memory, rocketing them to levels of performance never before seen in the laptop space.

These chips are part of the mobile “Core 2 Extreme” family, and along with optimized cache memory sport numerous architectural and power-saving tweaks that eke out considerably more performance than the mere 100-200MHz difference over the 2.4GHz models would suggest; sources predict that the 2.6GHz model (X9000 series) will perform upwards of 25% faster than the 2.4GHz (T8300) in most operations.

All variants of the new laptops include essentially the same motherboard chipset (”Apple-Customized Santa Rosa Refresh v1a and v1b” in the Macbooks and Macbook Pro respectively), with an 800MHz Front Side Bus and DDR2-667 memory controller.

Other than the storage space upgrades, according to reliable sources in Cupertino, the new iDevices use a somewhat different type of Flash storage that should offer substantial transfer performance improvements (especially for large files, since part of the difference is better buffering and sustained stream optimizations, as well as some improvements in the loading of large numbers of small {1024K or less} files — such as in a Web browser’s cache).

Overall, the iPod Touch should see between 50 and 300% depending on the size of the file, and an average of about 75-125% faster when syncing typical-sized MP3/AAC songs to the iPod.

The 16GB iPhone uses a somewhat smaller, lower-power/operating-temperature version of the same storage module and on average gets about 80% faster performance during a typical iTunes sync filling half the storage module (8GB) compared against the complete filling (also 8GB) of an existing model.

Interestingly, the max burstable performance of both devices is about the same (around 300-333% faster than current 8/16GB modules in existing iDevices), since they share similar buffer units and similar optimization routines for “write-behind” and “read-ahead” prediction.

Pricing hasn’t dropped as yet, however — the 8GB iPhone is still $399 new, $349 refurb.

Refurbished models will probably drop to $299 soon, and price drops for the new iDevices aren’t terribly far off; but for now, the $499 16GB iPhone is looking like a great buy for those who have been waiting for more/faster storage. You won’t be disappointed.

Depending on whether one is updating a PowerPC or Intel Mac, packages could vary from 250 to upwards of 400MB in size, and some on the grapevine believe its final weigh-in could be very close to five hundred megabytes.

Either way, it will be a huge download and there has been a lot of debate at Infinite Loop, according to reliable sources, as to whether the update should be split into multiple packages (the core system update, and individual updates to applications or components), hold back some changes for Security Updates that will follow shortly after the point upgrade…..or a more unusual solution, such as offering the update with a nominal pricetag of a few dollars on a CD-ROM disk for purchase at the Apple Store, to ease the burden on modem users or others for whom such a massive download is impractical.

For the rest of us, in the broadband age, a 500MB download isn’t such a big deal, but it will still be a huge strain on Cupertino’s bandwidth at a time when things like HD movie rentals and other new offerings are already rapidly expanding Infinite Loop’s bandwidth usage.

To prepare for the update, which was originally slated to have already been released but due to a huge changelog and the need for extra upstream bandwidth to be allocated for the huge surge that the Software Update release will bring, Apple’s network engineers have been frantically working overtime and on weekends to install new fiber, routers, servers and infrastructure to be ready for this.

One 500MB download might not be enough to bring Apple’s servers to a crawl on their own, or even coupled with the new HD movie downloads and ever-growing iTunes Store…..but Apple is also about to begin offering iPhone applications for sale and has a “major new .Mac related offering” to announce in March — about which we will soon be rumor-mongering, so stay tuned on that! — so adapting to all of these needs at once has proven quite a challenge for the usually unflappable network techs in Cupertino.

According to reliable sources, the final release of 10.5.2 will most likely come around build 9C40 and should arrive well before the end of February — quite possibly in as little as two weeks, if Tron’s latest “postcards from Silicon Valley” are accurate — so stay tuned for all the latest OS X update coverage and all the dirt that’s fit to print right here on Mac OS Rumors!

Those who pre-ordered models with hard disk based storage have received updated shipment date estimates, or in a few cases, shipment notifications with an expected arrival time around the 1st of the month.

We will be covering developments very closely, and many “streaming articles” with continuous live updates will be posted over the coming days as the first MBA’s reach the United States.

If you are a Macbook Air early adopter, or just want to weigh in on the latest developments, don’t hesitate to email us with your thoughts: rumors@macosrumors.com!

The sheer number of companies actively planning or already executing projects with target platforms like the modern day iPod Nano, iPhone/iPod Touch, and even AppleTV is much bigger than public perception seems to acknowledge. We’ve recently talked with a number of our friends in the gaming industry — from die hard Mac developers now focusing on “Cider” (DirectX –> OpenGL abstraction layer, allowing “Windows games” to be developed once and deployed simultaneously on OS X) development, to console companies and newcomers to the gaming world, virtually everyone is very excited about the future of game-style entertainment on Apple devices.

Cute little arcade games like those we see on the Classic iPods are all well and good, but a modernized Breakout with 3D graphics can only keep you amused so long; even Bejeweled gets old after a while.

Today’s gamers want rich graphical environments, fun smooth gameplay, and a captivating storyline. See the Ratchet & Clank series, or the recent post-movie “Simpsons Game” for the kind of game we love to play.

EA’s recent Cider-driven offerings Battlefield 2142 and Command & Conquer 3: Tiberium Wars are incredible to play, but you need the absolute latest Macintel hardware (no GMA950 or X3100 integrated Intel graphics owners allowed) and ATi or nVIDIA GPUs to join the Cider revolution and there’s still a significant performance hit versus running the same games (from the same install discs, even!) under Windows on your Intel Mac on these early-adopter Cider games — but hey, simultaneous release on OS X with nearly zero effort involved on the developer’s part is no small thing!

The kind of games that still draw tons of players on “last generation” hardware like Nintendo GameCube, the original Xbox, or Playstation 2 are great candidates for the iDevices. They require a lot less muscle than “modern PC” or PS3/Xbox 360-class console games, and many are adapted to small-screen devices like the Sony PSP so a move over to say the iPhone is a relatively logical one if the technical aspects can be overcome.

A lot of game developers are waiting for Apple to release its iPhone SDK next month, but others don’t want to wait for Apple to even get started. Many have found ways to either reverse-engineer the needed tools to begin developing for the “multi-touch iDevice” family, and others are quietly seeking to get their games onto the AppleTV platform either with or without Cupertino’s blessing.

Obviously, any product that tries to deploy on an iDevice like the AppleTV without Apple’s direct blessing and assistance is risky to say the very least! Apple could easily decide to break whatever technique the game used to get around Apple’s near-total lockdown of the iDevices’ application/system memory spaces, APIs and so forth.

Most companies interested in deploying to iDevices spoke to Rumors on condition of anonymity, and the embargo of many details of their products. But one developer, a former employee of Bungie prior to its buyout by Microsoft to launch the original Xbox with the original Halo and a very good friend of this site since its birth in 1995, has spoke with us in great depth about his plans to release a series of “mini games” starting with web-based offerings for the iPhone and eventually expanding into native games for any iDevice that Apple will let him deploy on legitimately.

Stay tuned for that interview coming up in the next few days; in the meantime, we have one other tantalizing tidbit on this topic to share…..

We have also been among the first to reexamine long-standing rumors of a major overhaul to the Mac Mini…..some have even gone so far as to speculate that the Mini as we know it is coming to the end of its lifespan and will be replaced with something categorically similar — but with a different name and striking differences. At this time, however, Rumors is confindent that the Mini, more or less as we know it today, will be around for a while yet — instead of replacing the Mini, we believe an all-new model designed to sit in between the Mini and iMac in the desktop product matrix.

This all-new desktop Mac, let’s just call it the Mac Air, for the sake of argument…..will take a lot of cues from the Macbook Air, sporting a smaller number of ports (though considerably more than the Macbook Air, due to different design constraints).

We expect it to retain at least one Firewire 400 port, perhaps even a Firewire 800 port, and there may also be more than one USB2 port.

However, there will be no internal optical drive (as with the Macbook Air, it will be an external option); internal storage will be similar to the Macbook Air: a micro-sized hard disk or a solid-state drive.

Originally, Rumors was given the rare opportunity to play with a prototype “Mac Nano” (this was before the “Air” moniker had been made public) about four months ago, and the resulting conclusions we took away from the titillating preview of sexy next-generation Macintosh hardware are only just now coming out from under intense embargoes, quite understandably put in place by cautious sources.

That prototype was based around 2.5-inch “laptop” sized hard drives and similarly mid-sized solid state storage; this is considerably larger, cheaper and faster than the 1-inch micro “ipod” sized drives in the Macbook Air and identical to what the current Mini uses for internal storage.

At that time, a massive overhaul of the Mini was said to move that machine up to full-sized “desktop” 3.5-inch hard drives, removing a major performance/value constraint on the machines while only increasing overall size by about 30% — most of that in vertical height, rather than horizontal width or depth. The overall appearance is still quite small, but a bit more reminiscent of the PowerMac G4 Cube than today’s Mini, with an all-over aluminum enclosure replacing the mostly plastic enclosure of today’s Mini.

We’ll be talking more about the new Mini soon; right now, it is primarily of interest only inasmuch as it affects the new midrange desktop “Mac Air.” The Air would be designed without internal wired ethernet, without an internal optical drive, and no active cooling system whatsoever — ergo, the solid state drive version would be completely silent and the hard disk based version very nearly so.

Energy usage compared to the Mac Mini or nearly any machine which performs nearly on the Mac Air’s level would be incredibly small.

The only more specific change was to Keynote: “primarily addresses performance issues while playing or exporting presentations.”

Reader reports on the updates are just now beginning to filter in; if you’ve updated iWork and noticed anything different or just had a thought related to the latest Software Updates, share your insights with the Mac community by emailing us! rumors@macosrumors.com

Any show-stopper issues will be posted to this article later as a series of “streaming updates” if necessary (so check back often; as with all of our new articles, updates may be added later along with moderated comments so be sure to browse on by again to get all the latest on this topic!)…..otherwise, reader reports on this latest iWork update will be posted later in the week.