Apple has been keeping developers busy with a steady stream of beta builds for OS X 10.8.4. The latest beta of OS X Mountain Lion 10.8.4 Build 12E33a was just seeded to developers.
Like the last build of 10.8.4, the release notes don’t contain anything significant, but devs will surely find new stuff once they get to digging through the OS. Apple asks developers to focus on Wi-Fi, Graphics Drivers, and Safari and says there are no known issues with build.
OS X 10.8.3 was released to the public a couple weeks ago after going through 13 beta revisions over a period of nearly 5 months. The next version of OS X should be revealed by WWDC this year, if not before.