They will probably be about equal. Just depends on games. Right now there isn't a single game that I would have to buy an xbox360 to play, and I have yet to read of a PS3 game which will justify the cost of that either. I have absolutely no desire to have Blu-Ray, or want to have anything to do with HDMI and all of the DRM surrounding Blu-Ray and Sony's proprietory attitude until everything gets hacked on all fronts.
I might consider buying an xbox360 if and when it becomes mod'able, and the price has dropped when PS3 is released - as long as it has at least 2 games I really want. Sony can suck on my left nut.
As for Nintendo, the Gamecube was trash IMO. But the Revolution seems intrigueing. I never would have thought I'd see the day where I would shun Sony, and be considering another Nintendo console