According to the folks over at
ign.com, this Spring will see the release of new content for both PC and 360 versions of Left 4 Dead.
The release is being dubbed the "Survival Pack" and will include a new Survival game mode, as well as two complete Versus mode campaigns. The article is unclear as to whether these are brand new campaigns, or Dead Air and Death Toll with added Versus mode. For PC gamers, this release will also include the much-anticipated SDK for the game, so aspiring developers can get cracking making custom content for Left 4 Dead.
At the same time, Valve are releasing a 'Critic's Choice' retail edition of the game, which will include all the new content of the Survival Pack.
Check out the
ign article for more details.