This is more than just a new desktop environment. This is a new windowing system. This isn't like replacing KDE or Gnome. It's like replacing gtk or qt (though of course qt and gtk apps will run under this environment I'm sure). Considering how opinionated and integrate qt and gnome have become as of late, I applaud that move. I prefer Pantheon myself, but think that the built in "desktop" should be separate from the standard library various apps run in (for several reasons). Let a thousand flowers bloom indeed.