Valve's Doug Lombardi has told CVG that we should expect a Left 4 Dead DLC announcement before the end of the summer for both PC and 360.

At a recent press event that took place in London earlier today, Lombardi told us, "We plan to keep supporting Left 4 Dead 1. There will be some announcements coming before summer's out about what's coming there, and then we haven't shown everything that's in Left 4 Dead 2 yet."

Lombardi added, "I think 8, 9 months from now once everything's been out for a while and everyone's had time to see the complete product of Left 4 Dead 2 and see continued support for Left 4 Dead 1, they may sort of see what we were up to and what the method of our madness was there."