Following the release of Mac OS X 10.6.8 Build 10K521, Apple team has now pushed third beta, Build 10K531, of the upcoming firmware update. There is no new feature included in this software update and Apple has asked developers to concentrate on several features such as AirPort, Graphics Card drivers, Mac App Store, QuickTime and VPN.
If you are a developer, you can download Mac OS X 10.6.8 Beta 3 from Mac Dev center. Apple is going to release Mac OS X Lion in WWDC event this year, which means Mac OS X 10.6.8 will be released soon for Mac users.
Download Mac OS X 10.6.8 Beta 3
Download the final version of Mac OS X 10.6.8 from here.