A YouTube video reveals that The Passing DLC (priced at 560 Microsoft Points or $7.00) won't be released before its previously targeted late March, 2010 date but is now set for a rather vague "spring."

The first Game Add-on brings the original “Left 4 Dead” survivors down south for a meeting with the “Left 4 Dead 2” cast, while delivering new single-player, multiplayer and co-operative gameplay, exclusively for Xbox 360 and PC.

Targeting an early spring release, “Left 4 Dead 2: The Passing” will include new co-operative campaign and associated narrative and new arenas for Survival, Versus and Scavenge modes, and introduce a new co-operative challenge mode.

Coming out this spring for Left 4 Dead 2 is the brand new DLC "The Passing," which contains:

• A Wicked Witch Bride
• A Gargantuan M60
• A Slashing Golf Club
• And Introducing The Fallen Survivor
• Meet 3 Left 4 Dead 1 Survivors
• New Game Modes

Introducing the AI Director 2.0, L4D's dynamic gameplay is taken to the next level by giving the Director the ability to procedurally change weather effects, world objects, and pathways in addition to tailoring the enemy population, effects, and sounds to match the players' performance. The result is a unique game session custom fitted to provide a satisfying and uniquely challenging experience each time the game is played.

In addition to the new campaign and boss monster L4D2 also includes "Mudmen," the "uncommon common" exclusive to the Swamp Fever campaign, and a few more of the 20-plus new items coming in the full product (cricket bat, AK47, and grenade launcher).

Featuring new Survivors, boss zombies, weapons, and items, Left 4 Dead 2 offers a much larger game than the original with more co-operative campaigns, more Versus campaigns, and maps for Survival mode available at launch.