Apple Seeds First Developer Build of Mac OS X 10.6.6

In a rather unusual move, Apple today seeded the first developer version of Mac OS X 10.6.6, known as Build 10J521, even before the company has publicly released Mac OS X 10.6.5.

As 9 to 5 Mac notes, there are no documented known issues in the build and the seed notes mention a focus on support for the forthcoming Mac App Store.

- Contains developer support for fetching and renewing App Store receipts. See "Validating App Store Receipts" for more details.

Interestingly, the Mac OS X 10.6.6 update is only 3.7 MB in size, suggesting only very minor tweaks at this point.

The unusual early seeding of Mac OS X 10.6.6 relative to its predecessor and the apparent requirement of Mac OS X 10.6.6 for certain Mac App Store functions suggest that Apple is likely fast-tracking the operating system update for release in the not-so-distant future.

Apple announced during its October 20th media event that the Mac App Store would launch on Mac OS X Snow Leopard within 90 days, and just yesterday the company began accepting submissions from developers for inclusion in the Mac App Store.