Had Sony not been so complacent this generation with the PS3 the 360 would not be on the market any more. Had the PS3 released with GT5, GOW 3 and FFXIII that would have been it, won against 360 before the "battle" even begun.
Price tag was high but I find it has to believe that the PS3 would still not sell great with such games released. Of course the key word here is "had".....