That is a great length for a FPS. Many of the greatest FPS are really short. From GoldenEye to Halo to Call of Duty. Replayability of the single player and the multiplayer modes helps a FPS to last a long time.
I beat CoD 4 and WaW both combined under 10 hours. But the addicting gameplay in both the single and multiplayer keeps me coming back for more.







