Apple has seeded OS X Yosemite 10.10.2 Beta 5 to developers. The seed, (build 14C99d), comes just one week after the fourth beta seed.
Apple is continuing to ask developers to focus their testing on Wi-Fi, Mail, and VoiceOver. Many OS X Yosemite users have continued to experience Wi-Fi issues, even after the November 10.10.1 update.
The new beta seed is available via the “Update” tab in the Mac App Store, and also via download from the Mac Developer Center.