After giving so much attention to iPhone and iPad, Apple has decided to give Mac its due.
Alongside releasing of OS X 10.8 Mountain Lion Developer Preview 2, over the weekend, Apple also seeded the first pre-release version of OS X 10.7.4 to developers for testing. The release arrived as Build 11E27.
There are reports that Apple asked developers to focus their testing efforts on Address Book, Graphics, iCal, Mail and Printing in the new build,. The new build also contains one documented known issue related to playing purchased iTunes content through QuickTime.
A separate pre-release version of OS X Server 10.7.4 is also available.
Source: Mac Rumors