Gears 2 will be a hardware seller. It will not be Halo 3, but it will still move hardware.

It will boost hardware sales, nobody can deny that. The boost just wont be that big

It depends on how much it was marketed. Halo 2 sold tons of Xbox's (relatively speaking). Same thing with Resistance 2.

Virtually any big game will move some extra consoles. But I don't see anyway this game could possibly move many consoles. There has already been a version of this game on 360. There has been Bioshock. There has been Halo 3. Seriously how many people out there could there be that would want this game that don't already have a 360? Not very many. It will just basically be people who didnt buy a 360 when those games I listed came out because it was too expensive for them at the time.

there will probably be a small spike, but not much.

not as big as Halo3

Halo 2 was only a hardware seller because the XBOX was limited in game titles and console sales before it came out.

On a mature system with several previous AAA titles and 20M already sold worldwide, I don't see GoW2 having a significant effect on 360 sales. Any small bonus is going to be lost in the huge increase all the consoles experience during the holidays.

Gears is not the kind of game that's capable of that. Also, why buy a 360 if the game will come to the PC?

Possibly. Considering the title will get a hefty amount of advertising many people will see the little 360 logo flash during the commercials which gives the console obviously more advertising. So it's probable that it will push some hardware. Especially considering the time tis releasing.

 Let's not even get started on that topic--it's got nothing to do with this thread.