It was also a touchscreen lappy. That made the Metro UI effective. But the UI struck me as MPD. Start Word with a tap on Metro ... and it flips back to Desktop to start Word. :-/
I also spoke to a sales person, who spends time in various retail stores selling Window 8 hardware talking to likely customers. Just within a few minutes of speaking with me I learnt two or three things about the Win8 Metro UI that I may never have discovered for myself. That's seriously bad. And I've used Windows since Windows 1. Heck even new MacBooks come with a little card showing you all the multi-touch gestures the touchpad supports. MS needs to do the same for all their new gestures.
That said, it is laudable that Microsoft is trying to push the desktop PC UI in a new direction. But it seems to have two basic problems: a lot of the design is not discoverable enough, and it was clearly hamstrung, which is undoubtedly why there is a Desktop mode. Some of the design relies on people being willing to try "standard" touchscreen gestures to do stuff, and the few things the salesman showed me struck me as trying to take the user a bit too far too fast.
But this is also the kind of problem I see elsewhere. You may remember my distate of Ubuntu Unity. I went rummaging on the 'net just to see if there was a way to put the Unity toolbar on the right. No: Mark Shuttleworth explicitly said "we will not make a way to do that". And then see all the conversations amongst users about How To Do Stuff since so much is not easily discoverable. (FWIW, I put Linux Mint 14 on my new lappy.)
I think we've been here before. I remember stories of users who did not realise the Windows 95 "Start" button was clickable. Going back further, I remember many many stories of users who could not grasp double-click on a mouse. Or even the dissociated effect of moving a pointer on the screen with a physical mouse.
All that said, the video did show a lot of "version 1" problems. Microsoft are notorious for those. If they are paying attention, they will come up with solutions for most of those and do a Windows 8.1 within a year.
Unfortunately, I don't see any signs that they *are* paying attention.
Wade.