Even as Mac OS Rumors worked to prepare our first in-depth look at developmental “alpha” stage builds of Mac OS X 10.6 “Snow Leopard” earlier this week…the first builds (10A250 and later) seeded to third-party developers in quite some time and the first to be nearly feature-complete hit the grapevine like a shock wave. We have modified this first Sneak Peek to incorporate some of these reports, notably on the most recent 10A261 seed, and will be posting smaller more frequent Snow Leopard updates in the days ahead.

To begin with, let’s review the straightforward nature of Snow Leopard’s mission: eschewing “innovation” at the user level for primarily under-the-hood upgrades, Snow Leopard is a one-year project that Apple has embarked on to catch up with its backlog of ambitious architectural and technological plans for the Mac OS X operating system.

Although focused primarily on optimization and the adoption of new hardware driven technologies like multi-core CPUs (GrandCentral) and advanced programmable GPUs (OpenCL), Snow Leopard does include a number of new software technologies — including a few that will be quite apparent from the user level and which will account for a visible feature set nearly as impressive as any OS release we’ve ever seen.

Granted, the number of new bundled applications and other routine major-release add-ons is far fewer than we’ve become accustomed to in previous versions of OS X, but in terms of the overall value that users will receive there can be little doubt — Snow Leopard is the operating system that Mac OS X was always meant to be.

As we’ll be similarly discussing in an upcoming article with regards to the Intel Core i7 “Nehalem” platform that Snow Leopard has been optimized in paralell with (and for)….2009 is the year that the full promise of the Mac platform that Steve Jobs, Avie Tevanian and Jonathan Ive have shaped since their triumphant return to/arrival at Infinite Loop in 1997, is truly realized.

Booting up the builds that various team members have had the chance to work with so far, the user is presented with a placeholder for the new “installation movie” — if you thought that OS X 10.5 Leopard’s post-install animation and associated soundtrack was impressive, we’ve been told by more than a few sources “you ain’t seen nothin’ yet!” but are still waiting on a leak of the film itself.

So far, we’ve been told that may not happen until the film is incorporated into late builds of Snow Leopard as part of the final complete-package testing…but that is weeks if not months away. Until then, we will hang on every report of its reputed awesomeness and await the opportunity to tell you more — not to mention eagerly anticipating seeing it with our own eyes….

Aside from that introductory film, the biggest feature that we are anticipating but haven’t yet seen is the new refined Finder. Clearly, in Snow Leopard 10A261 the Finder is benefitting from Grand Central enhancements under the hood and the many other improvements such as OpenCL’s greater ability to bring in the GPU’s muscle on a far wider range of operations than any previous version of OS X (which is saying something given the fact that no competitor has even yet today managed to compete with the original Quartz Extreme, to say nothing of present-day Core Graphics)….but even the most superficial probings into how the Finder is operating in these builds, as well the visual experience of using it hands-on, show it to be well short of what we have been led to expect in the new Finder.

Within the next two months at the outside, reliable sources highly placed within software development leadership at Infinite Loop say that the finalized Finder with an overhauled Cocoa codebase and a long list of architectural improvements as well as a small amount of visible streamlining will be fully integrated with the developer seeds being sent out. But that’s some time away; weeks, at a minimum, we’re told.

In the meantime, we get to see what the basic core Grand Central technologies can do….and it’s a very impressive thing to say the least. Not only is the next developer build (almost ready for seeding in the low to mid 10A27x range) already noticeably faster than the current 10A261 seed in many ways as debug code begins to be progressively stripped away….the main build tree, which includes the evolving “NSFinder” (a reference to the “truly NeXTStep” way of doing things) as well as the existing Carbon Finder which is rapidly approaching the obsolescence point, is a thing of beauty to say the very least.

Even for the non-tech-savvy consumer who has no awareness of what’s under the hood, Snow Leopard with its full streamlined appearance styling and Cocoa Finder will impress even if Apple wasn’t working so hard to make the first few minutes’ post-installation so remarkably dramatic with the new introductory movie and other slick “experience” work being done some of which we may not see right up until the final Golden Master…..but for those who understand what all this is about, the truly impressive features just don’t stop coming.

This Snow Leopard has teeth. And muscles. And claws. Big ones, all.

No icicle — or other conceivable obstacle — is going to slow this cat down.

Click through to the second page of this Sneak Peak for detailed listings of known features, rumored ones, and those we’ve been able to observe in current developer as well as internal builds….