Apple Seeds New Build of OS X Mavericks 10.9.3 to Developers
Apple has seeded developers (and those who wish to receive pre-releases) with a new version of OS X 10.9.3. The build number is 13D55, while the previous build is 13D43, which was seeded last week.
OS X Mavericks 10.9.3 has been in beta for a long time now, so we would expect a release sometime soon (current build of Mavericks 10.9.2 is 13C64).
Focus areas include: Graphics Drivers, Audio, Safari, Mail, Contacts & Calendar sync over USB in iTunes.
You can grab the update via Software Update if you are currently a registered developer on 10.9.3 or on the Mac Dev Center.
Those who are in Apple's new Seed program can also update via Software update, once it becomes available.