Left 4 Dead (Xbox 360) Easter Egg - Wow the Survivors Know About Steam

On the campaign Crash Course, which is purchased on the xbl marketplace for Xbox 360 owners, but for PC users it is automatically updated, on the first part you'll see a wall broken down and a pipe venting steam. Turn your subtitles on and listen to what the survivors say:

Zoey: Man, I just love steam.
Francis: Yeah steam's all right.
Louis: Steam is awesome.
Bill: Steam's great, isn't it?

Steam is the gaming software that Valve created for the PC where customers can use it to buy and download games and play them via this software. Steam is required for PC users to play L4D and all other Valve games.