Apple has just released OS X Mavericks Developer Preview 3 for download.
Take advantage of new features, like APIs that optimize the new energy saving technologies in OS X Mavericks, as well as new AV Kit frameworks, Sprite Kit, Map Kit, and many powerful additions to existing frameworks.
OS X Mavericks Developer Preview 3 is available as an update from the Mac App Store for systems running OS X Mavericks Developer Preview. To learn more, review the release notes in the Mac Dev Center.
Developers can get the update here.