I have used the Release Candidate and agree it is completely focused on touch-sensitive displays like tablets and cell phones. But, for normal desktops (say around of 90% of Windows installations), the UI adds more steps to perform basic functions by over-simplifying the interface. Especially if you have a lot of applications installed, and have to swipe through them. That would become extremely annoying.

Windows 7 is a huge success, but if Microsoft thought migrating people away from XP was difficult, migrating them away from Windows 7 will be nigh impossible. It really doesn't offer any compelling benefits unless you are using a cell phone or tablet.

Also, making the Microsoft Store the only way to acquire Windows applications is an even worse move. Windows biggest advantage was that anyone could install applications. How many companies will appreciate putting their internal applications on Microsoft's store?