Simple. there will be no growth.
Without the possibilities of dedicated servers for clans and casual players, nor the possibility of game modification to make tournaments possible, this game WILL NOT be well received by the FPS community at large.
I think COD4 was a fantastic opportunity for a game to finally take the crown from CS. and MW2 had a serious shot at making this a reality... but they screwed up BAD.
This also shows a serious lack of forethought on the side of PC game developers. Blizzard have pulled the same stunt with the new battlenet, completely getting rid of lanplay functionality. Games like WC3 and Counter-Strike were BUILT by the lanning community and the pro gaming community, and have survived much longer than their intended lifespans by a very dedicated and skilled modding/mapping community. Getting rid of this community only serves to make the game sell for a period of months, not years.
my 2 cents
