S.T.A.G.E. on 26 October 2014
Market, better press, better hardware, better price (at one time)) and momentum. Everything else is secondary. America loves FPS, but a lot of the FPS games they love will still be on the PS4 and will look better too. Word of mouth also helps.
As for the exclusivity issue, Microsofts definition of exclusivity is iffy at best. Its never means what it is supposed to because chances are their hottest games are not even made by them not contractually obligated to them even if they are third party. Nintendo's issue has truly proven that this is about third party power and not the power of first party.
