L4D2 promises to set a new benchmark for co-operative action games and become one of 2009's marquee titles, adding melee combat to enable deeper co-operative gameplay, with items such as a chainsaw, frying pan, axe, baseball bat, and more.

There will be nine avatar awards. Six have been confirmed so far. Here's what we know:

• Left 4 Dead 2 Shirt – A Left 4 Dead 2 shirt earned by winning 10 games of Scavenge
• Left 4 Dead 2 Shirt #2 – A Left 4 Dead 2 shirt earned by winning 10 games of Scavenge
• Depeche Mode Shirt – A sweet Depeche Mode shirt earned by rescuing Gnome Chompski from the Dark Carnival.
• Depeche Mode Shirt #2 – A sweet Depeche Mode shirt earned by rescuing Gnome Chompski from the Dark Carnival.
• Zombie Hand Shirt – A scary zombie shirt earned by killing 10,000 Infected
• Zombie Hand Shirt #2 – A scary zombie shirt earned by killing 10,000 Infected

Introducing the AI Director 2.0, L4D's dynamic gameplay is taken to the next level by giving the Director the ability to procedurally change weather effects, world objects, and pathways in addition to tailoring the enemy population, effects, and sounds to match the players' performance. The result is a unique game session custom fitted to provide a satisfying and uniquely challenging experience each time the game is played.

In addition to the new campaign and boss monster L4D2 also includes "Mudmen," the "uncommon common" exclusive to the Swamp Fever campaign, and a few more of the 20-plus new items coming in the full product (cricket bat, AK47, and grenade launcher).

Featuring new Survivors, boss zombies, weapons, and items, Left 4 Dead 2 offers a much larger game than the original with more co-operative campaigns, more Versus campaigns, and maps for Survival mode available at launch.

The Left 4 Dead 2 demo, now available on XBL, features gameplay taken from "The Parish" campaign, set in the New Orleans French Quarter. Playable by 1 to 4 players over local or Internet connections on both the Xbox 360 and PC (with two-player split screen available on the Xbox 360), the demo features all the new boss infected zombies and all the new melee weapons included in the full product.