Thanks for the drop OP but I had to stop the tape at glance view. As much as this is great to dream about, we are talking about Microsoft. They are simply not nearly as cool as that video. The only hope we could have getting close to anything like this, is for the VP of development allow devs get access to the API's to modify the look and feel. Much like what happens if you install Window Blinds from Stardock which they do allow.
This would also invite competition from Sony, Samsung, HTC, Dell and others to build Windows Phone handsets that go head up with Nokia. But that ain't happening as long as MS follows the Apple business model.
But on their own, Microsoft will never even scratch the surface of this much coolness. Especially as long as Joe Belfiore rides heard on development.
I'm convinced the only way they would take these kinds of risks is if the platform bumped up to the number 2 spot. At this rate, that is about a half a decade or more away.