No progress on USB 3.0 yet I think all of these issues will go away when Apple refreshes the Mac Pro and OS X gets official C612 support.
That's interesting about the Geekbench score. In addition to speedstep, you can get turbo working by adding -xcpm as a bootflag and 0x0306A0 as a fakeCPUID in your config.plist with USB 3.0 disabled. Should boost both single and multi-thread results!
Yea, I did that as well, geekbench score above also have that config.