I think it is amazing a company as big as MS has converged work station, tablet, phone and Xbox One UIs in such a short amount of time. Not saying I like all the changes, just amazed at the short amount of time it has taken.
I, for one, love the combination. When I'm coding, I'm nearly only in desktop mode. Browser with 20 open tabs, developer environments, consoles, the whole shebang.
Then, when I want a break, I hit start and open Twitter or fullscreen IE10. I'm suddenly on a tablet (with a dock that's always attached, but ok). My ongoing work is still there but hidden from my view and my mind. I stop using the mousepad, and browse with touch only. IE10 has a really excellent user experience on a touch screen, it makes Chrome on Android tablets feel ridiculously ancient.
Then, when I'm done with HN, private mail, and the weather, I hit Win+D and poof, my tablet became a PC again.
It may be a coincidence, but Microsoft essentially made a two-mode OS that precisely matches the two ways I use a computer.