Leading up to Left 4 Dead 2's Xbox 360 and PC release on November 17th, Electronic Arts has partnered with Kongregate to launch a four-week-long 10/23 - 11/20) meta game on the social Flash gaming portal.

During Infected Fury Month, a portion of Kongregate users is turned into zombies, while another group is designated as survivors. After learning the meta game's basic mechanics on a Left 4 Dead 2 branded section of the site, the zombies can earn points by infecting other players to turn them into the undead, while the survivors pick up points by training others to become survivors.

Infecting/training new players is accomplished through chat or by visiting a player's Kongregate profile page and hitting a Left 4 Dead 2 button. Survivors will have a glowing silver shield displayed on their avatar while the zombies will have their avatar and profile pages grayed out and spattered with blood.

Through the branded Left 4 Dead 2 area, Kongregate members will also be able to read situation updates, track which chat rooms are populated with zombies, and watch the infection spread. They can also switch their avatars into Left 4 Dead 2's four survivor characters or one of the boss infected (e.g. Charger, Wandering Witch).

"Infected Fury Month demonstrates the truly effective benefits of viral branding on Kongregate. We have over six million highly engaged gamers who will love getting involved with other players this way," says Kongregate's chief revenue officer Lee Uniacke.

"As Kongregate players experience yet another fun way to interact within the community, we’re building additional consumer excitement for next month’s launch of Left 4 Dead 2 on Xbox 360 and PC. Users on our site will be deeply enmeshed in the fiction of Left 4 Dead 2 by the time it hits store shelves."

With Valve planning to spend $25 million advertising Left 4 Dead 2's launch, I expect a lot more unusual promotions like this one.