www.bungie.net | halo.bungie.net | bungiestore.com
Halo and Halo 2 are some of the best selling games ever and lets face it, Bungie's other games were good but not sellers like the Halo games.They will have to make a fourth game.[Edited on 7/2/2006]
They dont have to do anything. I really doubt there will be a fourth. But they can make a multiplayer FPS only game after halo 3 with Masterchief.