After learning about the final two campaigns in Left 4 Dead 2, we now have a brand new trailer, either via legitimate leak or sneaky viral marketing. Either way, Valve seems intent on impressing us.Awesomeness may not be something that can be quantified in traditional units of measurement [these come close -- Ed.], but we're prepared to say that this Left 4 Dead 2 trailer contains at least 8 quarts of it. That's enough for the whole Little League team -- which, incidentally, shouldn't be anywhere near Left 4 Dead 2. It's rated M, you know. The rest of you, however, should watch it, and watch it hard. Warning: Minor plot spoilers, most of which involve killing zombies. [Via Shacknews]