They're definitely doubling...more like tripling down on this franchise. Its almost as if activision is slowly morphing into a nothing but cod publisher. Nothing else but skylanders has really been successful for them recently, other than the blizzard stuff. And blizzard is known for thriving on a small amount of super popular franchises, so that might be the model they're aiming at. They're not big on the social stuff like EA, nor are they trying to create a steam competitor. They seem to be distilling down to the very few things that work for them and jettisoning everything else.
Who knows where this leads. If I had to guess, just massive amounts of content for each game, subscription services, e-sports, metagame content, etc. They want cod to be a genre and/or a sport onto itself, transcend the definition of a traditional packaged game into an ongoing service. Now they've got 5 studios working on cod - IW, Sledgehammer, trey arch, raven and neversoft. Any more than one packaged game a year seems ridiculous to me, but each game can support a pretty huge amount of content.