Call of Duty hurt Halo or Halo 4?
Right after 2007, it was clear cut what people wanted, the quick paced FPS game was the popular thing. Halo, never being all too quick paced action didn't become the number one selling game, but certainly not dead.
I won't be surprised if a new style of games becomes the norm, specifically sandbox games. Skyrim being watered down so much, and selling so much is some evidence of that. If GTA V gets huge profits I won't be surprised if an open world call of duty game comes out.