Yes, I read the blog by Noel that showed the impressive numbers, but never wanted to install Windows 8 until it was released to manufacturing.
As we are a Microsoft partner, we now have the release version of Windows 8, so I installed it a couple of days ago and have been putting Sonar X1 (64-bit) through its paces.
All I can say is WOW!!!. Windows 7 was the best platform yet for audio, but Windows 8 absolutely blows it out of the water. I am going down to 32 buffers in my audio drivers and getting absolutely rock solid performance in large projects - this is unbelievable! In Windows 7, I could go as low as 128 buffers. I could use 64 buffers for very minimalist projects, but anything bigger and I had to go back to 128.
This is with the exact same MOTU drivers, using a PCIe-424 card and a MOTU 2408 Mk3 and 24I/O. It's like I just upgraded my PC and sound cards with something much more powerful.
My rig is a modest AMD Phenom II 1100t (six cores), but it feels like I just upgraded to the latest i7. I have so much more power up my sleeve and can go down to insanely low latencies. With Windows 8 and PCs just getting more powerful, I think we are nearing a par with hardware-based solutions like ProTools HD.
I don't know what Microsoft did under the hood, but they deserve a lot of kudos for optimising it so very much for audio. I'm in PC audio heaven.