The Left 4 Dead guys out at Valve have been holding off on a desire to release new DLC because of a few constraints, one major one being a gaping hole in what they already had on the table - there just wasn't enough.

That is until modder Matthew "2 Evil Eyes" Lourdelet showed them Cold Stream, his new community campaign mod that still isn't quite finished.

We loved 2 Evil Eyes and Cold Stream looks even more promising with innovative game play arenas and effects. Matthew has really shown that there are still plenty of new ideas in L4D2 modding.

We want you the community to be part of the process of taking his unfinished campaign and releasing it as DLC on the Xbox 360, PC and Mac.

You can read the full run-down of plans right here on the official forums, but this shows just how important community and the mod-community still are to Valve products. For those who can't be bothered hitting the link, you won't be seeing this DLC release still until at least after Portal 2 drops, and as always, even after that it'll be a case of "when it's done".