That has to be one of the shortest demos I have played, but well worth it. I will definitely be buying the full game. One recommendation to anyone playing it. Deselect the distancing focus option in the option menu. That will make distant objects sharper.
The only criticism I can see at the moment is that the transition from ingame graphics to FMV and back again still isn't seamless, but that's a technology limitation and nothing anybody can do about.