I think TitanFall helps Activision because it might get people interested in trying an online shooter that they might otherwise avoid. If they do get into it, then they will run into many CoD players and whenever the next CoD game comes out, that crowd will migrate back and draw some of those TitanFall players with them.
I haven't really seen anything in TitanFall that says it will keep the CoD fans away from CoD. I think it will provide them a short break from CoD and then they will go back. Plus all the next CoD has to do is include some mechs-mode or whatever and then they will be "ahead" of TitanFall in every other way.
TitanFall limited to 6v6 online competitive only which may be fine since it keeps the maps full with AI controlled people, but that also ends up being its biggest weakness. Those AI bots in the BETA are not exactly "cloud" controlled or smart or whatever. They are actually much worse than most easy difficulty shooter AI bots.
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I don't think exclusivity will change how CoD sells on XBO vs. PS4 if the two games are released many months apart like they are. It will be other game releases around the release of CoD that will change the ratios. Also, news articles focusing on 720p vs. 1080p and 30fps vs. 60fps type stuff can definitely have an effect as shown in the sales of Tomb Raider Definitive Edition.
