As quite a few people know, Activision and Infinity ward have been going for each others throat for a few months now, beginning with Activision fireing two Executives from infinty ward Infinity ward filed lawsuit for not reciving royalties from Activision, however Activision have countersuited Infinity ward regarding the apprent breach in contract.
During the trial Activision said that Development for the third title [Modern warfare 3] was delayed intentionally by Jason West and Vince Zampella, the two former Exectives of infinity ward and has apprently forced Activision to commit additional resources to Modern Warfare 3
So there you go people, Modern Warfare 3 is in development
-Tik