Multiple reasons:
1. Consumer satisfaction from the previous generation. The 360 had very few popular games for the last few years of its life while the PS3 was still releasing strong exclusives like The Last of Us, God of War Ascensions, etc. Consumers recognize the full support throughout the lifecycle and want the most bang for their buck.
2. Bad publicity from the competition. Microsoft's restrictions and their plan going forward was not received well by the gaming community and therefore was not shown in a favorable light in the media. Sony was.
3. Price. Don't really need to say this but $100 cheaper for a console that is supposed to be a tad more powerful just screams a better buy.







