It looks very streamlined and powerful - quite arguably more functional than today's iPad - but it's problematic that I don't see anything that makes anyones' life appreciably better. A Flipboard clone, mobile Internet, Twitter, Photos - nothing revolutionary. Really, really good, but nothing to give an iPad or Xoom owner buyer's remorse unless these are ridiculously cheap (I don't see how they'll have any price advantage over Apple or Googlerolla). Tablets will own this holiday season, which MS is missing out on, and remember that Windows 8 tablets will ship in the shadow of the iPad 3. Which, in turn, means that Android and iPad will remain the lead platform for large form touchscreen apps for the medium term future.
So: nice, but this doesn't stop their disruption.