Recently played with Windows 8 beta on a desktop PC. Not impressed.
Window 8 puts a Windows Mobile-like GUI on top of a more familiar Windows 7-like desktop. Furthermore, when you drill down to changes made to the desktop interface, it is sufficiently different (not better) from Windows 7 to be annoying.
It seems that Windows 8 wants to standardize the user experience across smartphones, tablets and PCs. Can it be all things to all people? Microsoft is not Apple. I am skeptical.