Valve has announced that Left 4 Dead on the PC and Xbox 360 will be receiving a few updates. The first set of new content will be the Left 4 Dead Survival Pack, which is due for release this Spring. The survival pack introduces a new multiplayer game mode entitled Survival and two completel campaigns for Versus Mode. A Critic's Choice Edition of the game is also heading to retail stores this spring, and will include access to all the content introduced in the L4D: Survival Pack.

PC gamers will also be receiving the Software Development Kit, which will allow them to create custom content that will be be discoverable via L4D's matchmaking system.The SDK update is also due for release this spring, and is free of charge to all owners of L4D on the PC.

For more information, please visit www.l4d.com