Apple seeds OS X Yosemite Developer Preview 8 build 14A361c on Monday, September 15, 2014. Apple also seeds OS X Yosemite Public Beta 3,
On a personal note, OS X Yosemite Developer Preview 8 is now the default Startup OS on my MacBook Pro. There were some bugs in the previous builds that prevent me from using OS X Yosemite as my primary OS.
OS X Yosemite is on track for release in October 2014, according to chatters within Apple.