Valve has announced the PC version of its new survival co-op game, Left 4 Dead, is available for pre-purchase via Steam, a online platform for the distribution and management of PC games.

"With just over four weeks until launch, Left 4 Dead is showing every sign of topping The Orange Box on both the PC and Xbox 360, at retail as well as on Steam," said Doug Lombardi, VP of marketing at Valve. "Our pre-sell numbers at retail have jumped to over 65% greater than Orange Box at the same proximity to launch, and we're seeing tremendous enthusiasm for the product in what promises to be another great year for gaming on both platforms."

Left 4 Dead is due for release on PC and Xbox 360 on November 18 in North America and November 21 in Europe. The worldwide Steam release will happen November 18. For more information, please visit www.steamgames.com

More information after the jump.

From the press release:

Left 4 Dead is a new franchise from Valve, and has earned numerous awards it march to launch this holiday, including "Best of E3" Awards from Game Infomer and Maximum PC magazines. Like the pre-purchase promotions happening at retail for the PC and Xbox 360 versions, those who pre-purchase via Steam will save 10% off the regular price. The pre-order promotions are part of a $10 million marketing campaign that includes television, outdoor, online and print advertising.

Set in the immediate aftermath of the highly-anticipated zombie apocalypse, Left 4 Dead features single player, multiplayer and co-operative gameplay modes. Next-generation artificial intelligence tailors the pacing and difficulty ensuring a different experience every time the game is played.