I did get a quick 10-odd minutes at a game show a while back and posted my thoughts earlier in this thread. The game was an ugly, jerky mess, with staples of bad visuals that I would have expected last gen (octagonal trees, etc). The segment I played was 'just another squad shooter', so possibly the game offers more than what was demo'ed. While obviously there's still a lot of time to fix these problems, this game was at the time still an '07 title that got jerked back due to the fact it would become another Lair.
I do think the premise could be nice, though, and I'd like to see it work well. I felt a similar response to Timeshift, which was originally nearly complete before they hit the drawing board from scratch..