Apple has seeded yet another build of OSX to developers. The new version of OSX 10.7.3, known as build 11D36 is focused on iCloud Document Storage, Address Book, iCal, Mail, Spotlight and Safari and has no documented issues.
Even the Delta-update of this puppy is a hair less then a GB.
(thank goodness that I chose iOS development instead) :)
Source: MacRumors
http://www.macrumors.com/2011/12/20/apple-seeds-os-x-10-7-3-build-11d36-to-developers/