Call of Duty: World at War producer on why it's not 'CoD 5'

Wondering what happened to the number "5" trailing Call of Duty and preceding World at War? Senior producer Noah Heller offered some insight into its absence, saying, "We're getting rid of the number in Call of Duty for a very specific reason: It's because we want you to know that when you're playing Call of Duty: World at War you're playing the best shooter, the best WW2 game ever. Likewise when you're playing Modern Warfare, likewise when you play any game that will be called Call of Duty."

Now, a handful of us have tried to parse that quote and, no matter which angle we take, it proves elusive. Is he saying that Modern Warfare didn't have a number in the title (because the game's box clearly says otherwise)? Is he saying that future Call of Duty installments, including whatever Infinity Ward is presumably working on, will also be sans number? Or perhaps, as rumored, Infinity Ward has renegotiated their relationship with the flagship title and any numbered sequels (all future sequels?) will be saved for them to develop?

We've sent our own inquiry into Activision for some clarification. We'll let you know what it throws back.