pretty obvious that late releases dont' ever do as good. Considering how much worse PS3 multiplat do compared to 360's. Did you really expect a multiplat that is delayed a year to do good
Most hardcore gamers fro PS3 have a 360 and got the game already. And again all multiplats do way better on 360 at start. I dn't pay attnetion to much long term, they may catch up but opening weeks are way better on 360 all the time