I think some heads must've rolled over at Ubi because that's a completely different game than what was teased in 07-08. To be honest, extended sequences of that "active stealth" thing likely played extremely boring - lugging boxes around and walking at the right pace to not arouse suspicion. It looks to me that the powers that be played it a stretch and just threw up their hands at how awful it was and decided to start from scratch. That's why we didn't get any news for the better part of a year. I liked the old games, partly because I'm the kind of slow meticulous gamer that really enjoys creeping around every single corner and killing every single goon in the level slowly (body count score be damned). Some of those new features look a bit gimmicky, but I could see it being really good.
To answer your other question though, I'm sure there'll be some form of co-op, although the story might prevent the co-op spy thing they had going previously. For me, I really only care about a solid single player experience so multi has never been a priority for me.
I hardly ever buy new games retail without some super sale or incentive going on (last one was RE5, then Ace Combat 6 before that), but this one looks to be a price-be-damned day 1 pickup for me.
