Single or Multiplatform?
Back in the day very few games were multiplatform. If you can actually think of any please tell me. I believe it is because of this that we saw some of the grea-*test*-('") games showing up. I think it's because of the competion. When your worried that people may not buy your game because they don't have the system you got to make your game so good people will buy the system to play it. Halo, Super Smash Bros, Devil May Cry. I would have no argument that these are the great games and they are all exclusives. Can you find one multiplatform game that was great?

Sou Calibur!!!

A rare exception but I think that generally multiplatform games are not as good as exclusives.

burnout 3 and 4. 9/10 series. and i know theres more, just can't think of any... need for speed is the most well known racing series, and they have always been for all consoles. EDIT: ah! prince of persia. all three of them. probably my favoprite multi-platform game. warrior within is the best in my opinion, with the first one being my least favorite, but still a great game. and your theory is an ok one, and it's hard to say what it is that make exclusive games good and multi-platform games good. many developers make a good game so the game will sell, reguardless of the console it's on. in fact, if its on more than one console, it'll sell even better. other developers make good games because they love their job. i know i would. :P and almost all good devs do it cause of both reasons. the reason exclusives are so common, is because many developers and studios pledge their allegance to that one system, or they prefer what that system has to offer. this can be a deadly thing though, as we've seen with the ps3, if there aren't enough consoles for it, the game simply won't sell, and ppl wont pay 600$ for a ps3 to play it. i would never buy a system just because one dev is making a good exclusive game. (resident evil 5...i'd have thought about getting a ps3 for it if it wasnt coming to the 360...but it would be a painful choice...) i'll buy it if it has many good games, like the ps2, the 360, and like the wii is shaping up to be. EDIT: an interesting thing i'd say to disagree with you the most, brannen, is ninja gaiden: sigma for the ps3. it will be an exclusive remake of ninja gaiden black for the xbox. why this conflicts with your theory, is that they are remaking this game purely for money, and this has no effect on xbox 360 owners, because they'll be getting ninja gaiden 2, an exclusive for 360. also, we'll know this is going to be an awesome game, because the ninja gaiden series always has been.