It's certainly a risk. I think of concept videos as being a close cousin to a technology demo -- stuff that conveys the idea about where you're trying to get to, even if you haven't gotten there.

I don't think that technology demos and concept videos are ill-founded in general, but I certainly agree that they can be. Microsoft Surface was a technology demo for quite a while, then it became a product... and then almost nobody bought it. It still looks cool. But while Microsoft used multitouch to build a cool thing that nobody uses, Apple used multitouch to change the world millions of devices at a time.

Then again, Kinect started life as a technology demo, too. And now it's a technology demo that's in the living rooms of millions of people. Without the demo, it would probably have been difficult to gather the resources to produce such a transformative product, even if it did get greenlit as a response to the Wii.

So I think it's more fair to say that they can be good or bad, and I think this applies to concept videos too.

If they have a plan of attack for the stuff in that MS concept video and the video helps them shepherd the resources to actually build it, then I think it's a good thing as long as it's something people actually want. You're right that there's a lot of fluff in there like the super thin bezel-free phones, but there's also plenty of things in there about embedding smarter context (Siri takes a modest step in this direction, and it's a great one), simplifying communications, and pulling different user interaction paradigms together so that it's not just "X or Y or Z" but all of the above, focusing on whichever one or two are the most useful at the moment. If MS can use this video as marching orders, and deliver products that do that, we all win.