Like most geeks, I have too many computers. But there are 3 that I use the most. There is the desktop that I am writing this comment from. It is running Windows 7 because the Windows 8 UI with KVM, while it technically works, is clunky. Win8 is designed for touch and I don't have a touch screen. And even if I did have a touch screen, my arms are not long enough to touch my screen.

The other one is my android phone. Clearly touch.

But the third is my multi-media PC which is connected to my projection system. I interact with the system through a remote control (although I hope for a Kinect in the future). Windows 8 can work on it, all right, but again, it's clunky.

The point I am trying to make is that different use-cases require different UIs. One size does not fit all.