here have been small pushes in this direction (e.g. the Ubiquity add-on for Firefox [mozillalabs.com] would let you type commands (like "map XXX" or "email page to XXX") and get immediately useful results), but for it to really work, from a user perspective, it has to be available in every application so that it's worth the cost to learn the new style.
I thought exactly the same when I saw the video, this is ubiquity for the whole OS. I have been a ubiquity user for a long time, in fact if you want to try it out there is still a version in development, and I simply can't live without it. So my advice would be to try out the system and *then* criticize the hell out of it, it might be great.
Also, I think that since most users of linux are already CLI power users, this seems like a great tool for the real users of Ubuntu, not the objective market that M. Shuttleworth thinks he has, but for the real one: linux users who don't want too much hassle when configuring the desktop.