Previously only given a “Spring 2010″ release window, Valve has let it be known that “The Passing“, the first downloadable content pack for Left 4 Dead 2, is shooting for a late March release on the PC and Xbox 360. This coming out of today’s X10 event where the content was shown for the first time and also where it was revealed that a new add-on for the ORIGINAL Left 4 Dead (not playable in L4D2) will follow about a “month or so” after the release of “The Passing“. There’s no details on that content at the moment, but we’ll be keeping our half chewed off ears to the ground.

Lastly, Valves Chet Faliszek stated to Kotaku that a L4D digital comic illustrated by Powers artist Michael Avon Oeming will be coming our way sometime after the release of “The Passing” DLC. Again, we’ll just have to get you updates once we have them.

So, looks like Left 4 Dead fans have plenty to look 4ward to…We’ll keep you posted as we learn more.