Call of Duty has been using the same engine since Call of Duty 2. So 2005.
Valve has been using the Source Engine since 2004.
The engines have been updated quite a bit, but they haven't significantly changed since their introductions. I don't blame Valve though since they focus more on gameplay than visuals. Call of Duty on the other hand recycles the same engine, the same gameplay, and often the same setting for each new game. Gets old.
But you really can't say all the competition has been lazy.
That's not a small list. Shows the amount of developers who've bothered to upgrade their engines.
Although Battlefield 3 is boasting a brand new engine. And while this is exciting, I don't think it'll be as significant as CryEngine 1 to CryEngine 2 was. Definitely eons beyond Call of Duty however.