It's really weird to see this argument now about how multiplats don't count.
Multi platform games were one of the biggest reasons the 360 outsold the PS3 in the US and the UK. People bought the system because its where their friends were all playing COD, BF, FIFA etc.
The danger MS is facing are early adopters jumping ship and having other people follow them - the $100 price difference being way more important than any exclusive on either side.
I think people are seriously overvaluing Sony's games on a sales level. Especially when it comes to Driveclub. A game that Sony already knew wouldn't do a ton, they didn't choose to put it on PS+ on day 1 out of the goodness of their hearts.