Valve is ready to bridge the gap between Left 4 Dead and its recently released sequel. The first set of downloadable content for Left 4 Dead 2, currently titled The Passing, will see the original survivors encounter the newcomers in Left 4 Dead 2, the developer announced today.

The Passing is scheduled for a release in "early 2010" (the press release also mentions "early spring," which means the actual release date could be a little off) for both Xbox 360 and PC.

You will meet the original survivors in The Passing, but you'll be playing as the new ones. Valve describes the upcoming campaign as "the most important campaign in the Left 4 Dead story."

In addition to a new story campaign, the content will include a new "uncommon common" zombie, melee weapon, gun and new playable areas for the Survival, Versus and Scavenge game types. Valve is also promising a new "co-operative challenge mode of play," but has released no details.

Pricing for The Passing will be announced closer to the launch next year, but as many will most likely note, the release makes no mention of the content being free on the PC. With Left 4 Dead, the first wave of downloadable content was free on both Xbox 360 and PC, but the most recent release, an additional campaign called Crash Course, cost $7 for Xbox 360 users. It was free on PC.

I've contacted Valve for clarification. I'll let you know when I hear back.

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