Apple's OS X Mavericks is nearly ready for its public release, which means that development on its successor is now underway. Mavericks, version 10.9 of Apple's venerable Mac operating system, is expected to launch toward the end of this month, according to 9to5Mac's Mark Gurman. When it arrives it'll include more than 200 new features, a few of which Gurman says haven't yet been formally announced — such as the ability to block phone numbers and Apple ID's in the FaceTime and Messages apps.

The report says Mavericks could reach Golden Master status (which means it's finally ready for consumers) at Apple as early as this weekend. The follow up to Mavericks, OS X 10.10 (it hasn't been given a fancy nickname just yet), will continue to bring design elements from iOS 7 and iCloud over to the desktop. It is believed that Apple will continue its longstanding tradition and announce OS X 10.10 next summer alongside iOS 8 — likely at WWDC 2014.

Update: As noted by 9to5Mac, the OS X Mavericks Golden Master has now been seeded to developers.