This morning Activision announced a number of details regarding the latest installment in the Call of Duty franchise. Call of Duty: World at War will allow players to live vicariously as both the side of the US against the Japanese and the Russians against the Germans. The most anticipated feature, however, is the four-player co-op mode. On the PS3 (and Xbox 360) version, players can choose between a
multiplayer four-player split-screen offline co-op mode or a four-player online co-op mode. Finally, there is experience points to be earned in both online modes, with a difficulty level that "will scale dynamically to provide a deeper level of challenge," so how challenging it will be depends on the experience level of the player and the player's comrades.
[Update: There is a four-player offline co-op mode and the wording has been changed to clarify this.]