As I recall - the last L4D2 night you organised you played one match and then piked out

Valve has announced the next chunk of DLC for Left 4 Dead, which should please fans, as it's compatible with both Left 4 Dead 1 and 2.
Entitled 'The Sacrifice', the next episode in the ongoing Left 4 Dead saga will see another of its ragtag band of survivors following the same fate as one of Left 4 Dead's original cast in 'The Passing' (we won't say who to avoid spoilers). Yes someone will die, but who has their brains devoured this time around will be entirely down to you.

The Sacrifice will not only act as a prequel to the events in The Passing, but will also include a revamped No Mercy campaign from the original Left 4 Dead complete with the additional special infected and weapons that were introduced in Left 4 Dead 2. Bonus!

Making the announcement via GameTrailers TV, Valve's Chet Faliszek revealed that The Sacrifice will be available on October 5th, but a price has yet to be confirmed. You can probably expect to pay 560 Microsoft Points again though, given the price of previous L4D add-ons.