I got my new 4930k and got the system up and running in Windows. No issues.
Haven't been able to get into my 10.8.5 install. I also tried booting into Mavericks.
My issue is that I get through a verbose boot fine, but then I get a blackscreen.
I've tried a number of bootflags, mostly different combinations of:
-v npci=0x3000 GraphicsEnabler=no cpus=1 PCIRootUID=0
tried 0x2000 as well... all the same result. I'm going to try a fresh install of 10.8.5 and see how it goes.
Anyone have luck with Ivy Bridge-E yet?