I've a sneaking suspicion that these won't stay up on GameTrailers, so take a look while they're hot. Past the jump there's a whole bunch of shakeycam videos of Left 4 Dead being played, and they show off some of the best stuff in the game. Left 4 Dead, in case you weren't paying attention, is the 4-player co-op zombie shooter multiplayer type thing from Valve. I've played it, it's entirely awesome, and it's scheduled for release on November 4th.
This one shows someone being tongued to death by one of the boss infected, The Smoker. See how the co-op humans all yell to each other contextually - "Reloading!" - that's automagic, and doesn't require you to do anything.
This next video shows the player being vomited on by a boomer - another boss infected - something which brings the rabid zombies a-screamin' and a-rendin'.
The third clip has some intense firefights going on, and a couple of boss infected attacks. Watch out for the smoker hanging one of the players by the neck right at the start. Players can be boss infected, but the AI performs the same kind of ambush tricks.
Like Max Payne, the Left 4 Deadites do like those tasty pills. (To ease the pain.)
Of course this all old news to me. Yeah...