Valve has stated that more Left 4 Dead DLC will be announced before the end of the summer for both PC and Xbox 360.
"We plan to keep supporting Left 4 Dead 1," Doug Lombardi told CVG at a press event in London today. "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.
"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."
Speaking to OXM at the same event, Lombardi confirmed a multiplayer demo for the sequel, and it's expected sometime before the November release.
"With Left 4 Dead in particular we've found that word of mouth really is the strongest thing," he said. "With Left 4 Dead 2 we plan to do a demo before the game comes out that'll have multiplayer in it. And hopefully we can continue the free weekends with the full game post-launch."
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