Despite the previous build of Mac OS X 10.5.7 code-name “Juno” appearing nearly ready for release within days (it’s now been over a week), Apple has delivered a new seed — build 9J56 — to developers, and it looks like a little bit of work still remains before we’ll see 10.5.7 in Software Update.

From Apple’s build notes on 9J56, the following headline changes were highlighted for developers to test against:

• Fixed an issue when a process is killed or crashes while using AFP
• Bluetooth compatibility and stability fixes
• Crash reports missing application’s short version info fix
• Crash log file missing machine’s name fix
• Fixed an issue with Personal File Sharing where an AFP volume was not a valid Time Machine backup disk

Although these seem relatively minor, set against the full “Juno” project changelist which is nearly 200 items long at this point (and doesn’t include subtle tweaks of relatively little interest to third party developers for whom the change logs are written)….of particular note is the focus on Bluetooth in this build.

According to reliable sources, the understated phrasing of the changelog item — “compatibility and bug fixes” — hides the fact that nearly all of the previous ten days’ work on the part of the Juno team (enhanced by several members of Infinite Loop’s Bluetooth engineering team ’sitting in’ on related work this month) was focused on that Bluetooth code.

Specifically, with Apple hard at work on support for the emerging Bluetooth 3.0 standard and new combination 802.11 Wi-Fi/Bluetooth hardware in several of its prototype products, 10.5.7 is being prepared to act as the initial shipping OS on new Macs that will include Bluetooth 3.0 this summer.

Since the next (most likely final) iteration of Mac OS X 10.5 “Leopard,” 10.5.8 (roadmap code-name ‘Voyager;’ working code name believed to be ‘Minerva’) will apparently not be released until August or September….this puts 10.5.7 squarely on tap for any Macs which might ship before 10.6 “Snow Leopard”.

The timing of new Mac announcements/shipping, Snow Leopard’s release, and the necessity of system compatibility for BT 3.0 add-on devices in existing Macs all factor into the significance of this news….but either way, whether the new code in Juno is critical to new product releases or not, the effort that Apple is putting into the new technology speaks to the company’s commitment to the standard.

We expect to get our first taste of Infinite Loop’s Bluetooth 3 implementations at WWDC (June 8-12th), when developers will be encouraged to adopt the technology in their applications…..and given all that we now know on this subject, it would not come as a surprise to Rumors if all the new iDevices announced at WWDC shipped with combination 802.11n/Bluetooth 3.0 wireless chipsets.

Will they be the new Broadcom chips with built-in FM radio? Or another solution from a different supplier?! Stay tuned as we break out the big shovels and dig deeper into this new-found dirt! If you’ve got questions, comments, or just have something to say….don’t forget to follow us on Twitter, drop us a line by email, or simply fire off a comment using the form below!