Stealth can be good. If it's rewarding. Games like Bioshock and Farcry 2 completely fuck it up because it's so damn broken. Good games that make Stealth work, like Thief, or NOLF, are actually good, because the stealth mechanics are actually rewarding.
Whoever is talking about bad AI, stop. This is the innovation list, and bad AI isn't an innovation. Swimming under water is stupid, but if you just do it like Far Cry 2 it's fine. I agree that stealth can be fun if the developers do it right. And I totally agree about escort missions, I don't think any game has done that right. They should make an escort mission where someone escorts you.