But if you have the money, why not?
The Xbox is great for FPS, action, and adventure, while the PS2 specializes in RPGs, while it does offer every kind of gaming available (sp?) And a lot of people will buy a console for specific games, for instance, tons of people went out and bought a Xbox just for Halo, while a lot went and bought PS2 for GTA, and a Gamecube for Metroid Prime.