User blog comment:Bovell/Treyarch begins staffing for next project. MW3 announcement next month./@comment-120.28.64.77-20110331055726/@comment-2137624-20110403072934

No, CoD1 was id Tech 3, CoD2 was buildoff of id Tech 3, CoD 3 used a internally built engine, CoD4 used a new upgraded id Tech 3, WaW used basically the game CoD4 engine, MW2 used a updated IW engine and BO used a little updated WaW engine.