Have you seen the Metro UI for Windows 8? God, I absolutely can't stand that they're mixing tablet UI's with the desktop. Do you think Microsoft is getting desperate for the mobile market?
Microsoft is very confused, and they continue to be muddled up by the Windows Everywhere Steve Ballmer disease.
That said, I think Windows 8 tablets are going to be the first real competitors to the iPad. Windows 8 seems to be competitive with iOS for touch screens, and I think if they get prices down low enough, you'll see a lot of people actually using them.
I think Windows 8 on the desktop is going to be a debacle, though. No matter how good Metro is with a mouse, the dual-mode compromised approach MS has taken with Windows 8 means that most people are going to see it as "Windows 7, but with this stupid splash screen I have to exit out of when I turn the computer on."