Apple continues to release developer seeds of Mac OS X 10.6.3 for testing, but judging from those using it, the official release may be getting close.

On Tuesday, Apple made Mac OS X 10.6.3 Build 10D571 available to developers, and MacRumors managed to get the details, courtesy of website iPhone in Canada. Cupertino has asked developers to “focus their testing on Graphics Drivers, iChat, Quicktime and Fonts.”

Among the two biggest issued addressed with the new developer seed:

- Issues addressed that caused background message colors to display incorrectly in Mail when scrolling
- Issue resolved that caused machines using BTMM and the Bonjour Sleep Proxy to wake unexpectedly

A known issue affecting Software Update has also been documented, and to test the problem, Apple is having last week’s Safari 4.0.5 update offered again in the new build.

It’s been 11 days since the last developer build of Mac OS X 10.6.3 was seeded, and MacRumors is predicting “a final version to the public in the relatively near future.” While Apple’s update schedule can be a slippery fish to catch, as developer seeds get released at a faster pace, it’s a good sign that development is winding down on a particular release.

Apple released the final Mac OS X 10.6.2 update in early November and began seeding 10.6.3 to developers in early January.