Valve is looking to expand its multiplayer-focused Left 4 Dead in 2009, sending word that survivors should look forward to a variety of bonuses throughout the year. First up is the L4D Survival Pack, which is set for a spring release and promises to add a new game mode, "Survival," along with two more full campaigns for Versus mode. If you've been holding off on purchasing the game (there's no good excuse, by the way), you'll be pleased to note the upcoming release of a "Critics' Choice" version of the game, which includes the aforementioned DLC.
The next tidbit is only for the PC gamers: Valve says it's unleashing the Source SDK, for free, this spring. It will allow PC gamers to customize and create their own campaigns and ... did we mention it's free? We imagine those folks making that Resident Evil 3 campaign are especially excited about this.
Sadly, there isn't any info as to how much the L4D Survival Pack will cost, but we'll pass along word as soon as we can.