Apple has released a new build of Mac OS X 10.7.3 rather the third build i.e 11D33 to testers not developers. Apple has asked the testers to mainly look on Apples own applications like iCal, Address Book, Mail, Spotlight and Safari. The 10.7.3 will be released soon to public as its in the last stages of work.
The public release will mix minor bugs as usually.
Below are the release notes by Apple
You will not be able to revert back to your previous system after updating. Please install this update on a system or partition you are prepared to erase if necessary. As this is a pre-release build, it is not advisable to use this software on a production system with information on it that you depend on for your business. You need to understand the OS X Lion Instructions for reinstalling the OS. Please read this entire article before installing the software update,http://support.apple.com/kb/HT4718.
REVERSIONERS ARE NO LONGER REQUIRED – The 11D33 Delta and Combo will install on top of the previous 11D16 and 11D24 seeds as well as our previous GMed systems.
Software Update Delta Installation
Install the delta version of OS X 10.7.3, 11D33 on your OS X 10.7.2 11C74 GM Build. Detailed Installation information can be found on the AppleSeed Discussion Board.
SoftwareUpdate Combo Installation
Install the combo version of OS X 10.7.3, 11D33 on your OS X 10.7.0, 10.7.1, or 10.7.2 GM Builds. Detailed Installation information can be found on the AppleSeed Discussion Board.
• Address Book