Let's see how much auteur-ship really influences game purchases (probably very little). If Activision loses its strangle-hold on the 'realistic' fps market very soon, it's because the bottom fell out.
I think the bottom will fall out because Activision is going to milk Call of Duty until it's utter garbage that no one wants to play. Then these ex-Infinity guys will come along and probably release something notable again. Then it's goodbye Activision.