As for the Metro full screen not a good choice for many apps such as Skype, I hope they fix that on Win9. Honestly the foundation is already there. Metro can already do tall strip mode. All they need to do is simply put those Strip Metro in a none-resizable window frame and put it on the work space desktop, all done.
How would that be different from today? Pin Skype to the side in "tall strip mode" and have the desktop as your main "app". Or do you mean doing that with multiple Metro apps?