I can't believe people are saying bye bye Halo... Xbox 360 is shooter central so there isn't really a lack of competition you know.
Halo 3 will still demolish any shooter that comes to PS3/Wii for a long time when it comes to people online playing it.
It will be interesting how GTA4 DLC does...
But yeah, well done Infinity Ward...COD4 is a great game. (although as most hyped games...not as good as the sales would indicate)