nice job for call of duty. The new call of duty coming out will probably not affect its sales as much since it won't be a modern warfare. I have a feeling the next call of duty will tank after a lot of people were dissapointed with world at war, other then nazi zombies.
The only game that has any chance to outsell mw2 on 360 is halo reach. Reach might have better week one sales if they advertise it to hell like i think they will, but unless there is good word of mouth like there seems to be with MW2, sales will go down very quickly and it won't be able to pass it.