It's looking like the San Diego Comic-Con is becoming more and more important to game publishers. Witness the news that Valve will be showing up at Electronic Arts' Comic-Con related event to show off a never-before-seen campaign from their zombie co-op shooter sequel Left 4 Dead 2.

The campaign is titled "Swamp Fever" and as you can see from the new screenshot above it definitely takes place in a murky and dark environment. The demo will actually take place outside of the Comic-Con's convention center crowds; it will happen at the EA Gaming Lounge, located at the Hilton San Diego Gaslamp Quarter Hotel at 401 K. Street. You can check the lounge out from 2-9 pm July 22-25 and 12-5 pm on July 26.

A note on the Dragon Age: Origins forums has more info on the EA Gaming Lounge, revealing that people will also be able to get hands-on with BioWare's upcoming RPG along with Battlefield 1943, Battlefield Bad Company 2, and other upcoming EA titles. Best of all the event is free for anyone to attend; you don't need to have tickets to the sold out Comic-Con to show up.