You really shouldn't be reading this, you should be saving the world from the impending zombie apocalypse with your friends in Left 4 Dead. If perhaps you are on the fence about purchasing the aforementioned game, then we have a few reviews from around the interwebs that may change your mushy mind.
IGN - 9.0 - "Having said that it does redefine co-op in a certain way. Or, at least, it admits what co-op's really about underneath all the superficial buddy back-slapping, and makes a bigger deal out of the underlying selfishness. When you play a co-op game you're still playing to win, still playing for your own ends. What Left 4 Dead does, at least when you're playing as the human Survivors, is make your survival absolutely, 100% dependent on your companions."
Team Xbox - 9.1 - "Well, at first it seems simple, because they’re mindless zombies after all, all of whom lope along as if in a stupor and most can be taken down by a single loosely aimed shot. However, it gets more interesting when something enrages them, such as you looking at one of them without firing or if you happen to trigger a car alarm. Each chapter has one spot where you need to activate some mechanism that’ll help your party get toward the safe house—but that activation also sparks an thundering zombie stampede almost as bad as a mall opening on Black Friday."
GameSpy - 4.5/5 - "Once you have friends on your side, it's one hell of a ride. With dozens of zombies swarming you at any given moment and the yells of your friends echoing in your ears, the action in Left 4 Dead is as intense as any game in recent memory. This is one of those games in which you'll need to use teamwork and communication if you hope to survive, as things have a tendency to go FUBAR as soon as someone decides to make a go of it on their own. Friendly fire is always on, so you have to watch your aim. "
Do you hear that ladies and gentlemen? That is the sound of inevitability. There's simply no excuse now, you must have this four player co-op title. We'll have our review up early next week, until then - grab a shotgun.