Multiplatform games selling better on PS3 speaks volumes about PS3 attach rate since for most multiplayer games ability to play with your friend weighs heavily in what version you are going to buy (Xbox360 or PS3)? Since, there are 8 million more xbox360 players chances are more of your friends have xbox360 than ps3.
I am actually pretty surprised that PS3 is not far behind XBox360 in terms of sales of multiplatform games considering X360 has a nearly 30% more installed userbase unless the user base is the same and more x360 were sold as 30% people had to buy another one ;) .









