Four player co-op in Killzone 3?

According to CVG, there will be a bunch of different co-op modes in {Killzone 3} - not only will you be able to play the campaign together with a friend, but also play together with three other persons in a special mode with various co-op missions.

CVG's source says that there will be vehicles in multiplayer this time around, and that the game should be out in May 2011.