The PS3 was released a year after the XBox 360, cost $100/$200 more than the XBox 360 to buy, and Sony was still losing hundreds of dollars to manufacture the system, and after developers have spent over 4 years working on the system the benefits over the XBox 360 are minimal; and the XBox 360 still regularly receives the better version of games because how unsuited the Cell processor is to game development.
Within 2 years the next generation will begin and soon after all three manufacturers will have systems with real-world performance that greatly surpasses the XBox 360 and PS3; and rapidly support from third party publishers to create quality games for these systems will disappear. Most of the games which continue to be released will be the occasional sports game and licensed tie-in which will (mostly) be developed by inferior teams within inferior studios. Or to put it another way, the best the PS3 has to offer in game has already been seen ...
Now, if you want to see how much of a mistake the Cell processor was and how pointless Blu-Ray was compare the advantage a year gave the PS3 to the advantage a year gave the Gamecube and XBox over the PS2; and neither of those systems cost nearly as much to manufacture as the PS3 cost Sony.