Activision has broken up Infinity Ward completely. Once the new map pack is finished for MW2 they will be given their outright release. Modern Warfare 3 and the other two in-progress Call of Duty games will be split between two Activision studios that have never had anything to do with the franchise.
I'm sure it will happen. its to big of a franchise to let just go down the drain. Activision is a Company and they know what franchises make them money. They'll spit out at least one more MW before they give up on it.