The E3 show floor is packed to the gills with gamers from around the world, many of whom are waiting for their chance to play Valve's Left 4 Dead 2, the rapid-fire sequel to a game that only came out last year. Already played Left 4 Dead? Awesome! Then you'll be able to jump right in to its follow-up. Left 4 Dead 2 plays just like the original -- at least at first. It's still you and three other (albeit new) characters, blasting your way through zombie hordes as you try to escape to safety. And yes, the AI director is still tuning the excitement to epic proportions.