There have been a number of blogs about the Windows 8 Metro look and feel, some positive some negative. In my own experience if you use the OS from a touch enabled device the experience is good, try using a mouse and it is frustrating. No doubt it will be possible to switch between interfaces however what I would like to see is the intelligence in the operating system to detect the type of device you are using and then present the interface based on the result. Between devices if the user choices and settings can be synced then I think Microsoft will have a real winner. In my opinion leave it up to admins to decide who gets what and when and force users to use an interface they are not happy with and the operating system will be rejected.