"From the playtests, I think it's anywhere between 8-10 hours," said ter Heide."The fastest guy did it in about eight hours, but on average it was about 10 hours."
8-10 hours has become the standard length for a first person shooter campaign - though Call of Duty games tend to be shorter. Halo: Reach, for example, also ran roughly 8-10 hours. In this day and age, most of the gameplay experience for a shooter is felt in the multiplayer experience, which Killzone 3 hopes will keep the player hooked.