Left 4 Dead 2 New Campaign - Cold Stream
L4D2 just released a new Campaign called Cold Stream. I didn't know they were coming out with it until I played today and Blackleo pointed it out.
Here is announcement: Left 4 Dead Blog
It's still beta and they have a lot to work out. I've found most people get stuck between rocks in the stream and charger registration is really bad in some parts of the map and crazy good registration in others. Hopefully the real DLC is better.
I want them to come to come out with Dead Air though. My favorite map from L4D1.