In a recent interview, Guerilla Games has confirmed that there will be no split screen in Killzone 2, neither co-op nor versus. The game's director Mathis de Jonge explains "technically it would be quite difficult to implement it... that would cause issues with teleporting players... gamers will [still] have plenty to sink their teeth into". Not only that, but common sense would indicate that, being the technical juggernaut that Killzone 2 is, the graphic quality of the title would also have to be severely compromised as well in order to do this. This has been done in similar titles, such as Resistance 2's epicly proportioned online co-op mode.
Rumors have been floating around for months of DLC that would contain bots and/or a co-op campaign. Though these rumors were always promptly quelled, Guerilla wanted to smash these rumors once and for all.
Killzone 2 is a first person shooter developed by Guerilla Games. The highly anticipated title is due out February 27, exclusively for the PS.