Its been on the Xbox for a few years now aswell but not on the same day as its Sony release. I'm glad its on both systems because now I won't have to pay $600 for one game.
Just because you're a sony fanboy and don't want to admit that they're in a downward spiral doesn't mean it shouldn't be released on other systems. If Sony had announced the game the day before this wouldn't of been as big of a shock.