Well, Windows 8 probably has the best handling for screen sharing out of any tablet OSes- the whole "snap" functionality is very clever. Not so for desktops, of course.
personally, i don't care about Windows on a tablet ... i develop software and create graphics using a 24" monitor ... i don't like seeing full screen anything. Windows 8 is a disaster for serious content creators and productivity professionals like me.
What, all because of a fullscreen start menu? Start8 lets you configure it to open in a smaller popup overlay if you'd prefer. Or indeed have an old Windows 7 style menu instead.