In an age of increasingly large multiplayer modes, why do Left 4 Dead and Left 4 Dead 2 only offer four-player co-op? ...oh, that's why.
Now, I've been playing quite a bit of Left 4 Dead 2 these past few days, and it's safe to say that I'm enjoying it quite a bit ... but I won't say any more, lest I spoil the experience tomorrow. Crap, I've already said too much!
But in case anyone ever complains to you that the four-player co-op in the Left 4 Dead games - and the only eight-player Versus mode - is way too small, and Valve needs to get with the times because MAG is clearly going to be the best game ever, you should just show them the above video. This is what happens when you hack L4D2 to allow sixteen Survivors to all play together.
Methinks this isn't exactly how Gabe Newell intended the game to be played.