OK - this is actually pretty cool. I had a chance to use something similar a few years ago when I was working with the FBI - it was a map-based system, run off of the satellites, where you could use your fingers to zoom in and out and move the map around. At the time, I was more impressed with the real-time satellite images (and I was looking at the non-classified version), but it was pretty cool to interact with this device without using a mouse or keyboard.
Now that Microsoft is bringing this to the consumer market, it actually looks pretty exciting. I really like the way it seems to seamlessly interact with other external devices, like phones, music players, and credit cards. Pretty cool stuff. I can't wait to get my hands on one.