Microsoft seem to be taking a big risk with the Metro UI. I'm still not sure on it myself but if these reports are true and Windows 8 does in fact have a significant performance advantage over 7 than it is definitely worth a look!
In the past we've used many different benchmarks and apps to measure the performance of DirectX. These have been largely focused on 3D games,' Copeland explains. 'While games are still very important, we knew that many of these existing ways to measure graphics performance did not tell us everything we needed to know for graphics-intensive, 2D, mainstream apps. So, we created new scenario-focused tests and metrics to track our progress.
I'm not going to go into too much detail here because the blog is very detailed and interesting and is worth a read. If you like graphs there are plenty in the blog too! Standard desktop rendering is shown to have a significant performance increase over Windows 7. You can see for yourself in the video below!
How this will affect games is another question but by the looks of it there could also be an improvement in Windows 8.
TIR enables Direct2D to spend fewer CPU cycles on tessellation, so it can give drawing instructions to the GPU more quickly and efficiently, without sacrificing visual quality. TIR is available in new GPU hardware designed for Windows 8 that supports DirectX 11.1.
However, will the Metro UI turn off many potential customers despite the increased performance? Personally I am willing to give it a try and see. However, the true test with be whether it has a high enough WAF or not.