Apple has released the 6th developer preview of OS X Mavericks to Mac developers. No new features are expected in the new build, as typically these updates focus on bug fixes and minor refinements.
The latest version weighs in between 1GB-3GB, depending on hardware, and is recommended to install for all users running OS X Mavericks Developer Preview 5. The quickest way to get the update is from the Mac App Store via Software Update.
The final version of OS X Mavericks is expected to arrive for public use sometime this fall, possibly alongside the release of new Mac hardware. Mavericks includes many new features and improvements for Macs, including Maps, iBooks, an all new Safari, tabbed Finder windows, and significant improvements to power usage and consumption which could offer meaningful improvements to portable Macs battery life.