OXM reports that the Xbox 360 version of Left 4 Dead will include four-player co-op and eight-player four-on-four versus matches on Xbox Live or System Link and will only be released for 360 and PC.
While split screen mode has not been announced yet, the game promises that players can play online or hook up as many as eight 360s to get a game going either over System Link. OXM reports that the 360 version still has a way to go before it catches up the the PC build but they will be releasing together.
OXM also confirms that there will be no PS3 version but no reason was given for the exclusivity of the title. Left 4 Dead is a co-op zombie shooter where four human players face off against four zombie players each with their own unique items and abilities.
Kombo will keep you updated.