I was working on a Win7 computer tonight, and happened to hit Win+Tab instead of Alt+Tab. What struck me as odd is that when you hit Alt+Tab, the first instance of Tab pushes you to the next window. However, in the Win+Tab instance, the first instance of Tab merely pushes you to the screen to go to the next window. So in order to switch to the next window, you have to push Win+Tab twice instead of once. This may seem like a small thing, but to someone who uses Alt+Tab frequently, this is a major flaw and the major reason why I will not use Win+Tab in Vista or Win7 for the foreseeable future.