I think they both benefited from each others mistakes. RROD still seemed to be really bad for Xbox even a couple of years ago.
But both Sony's price and the Xbox 360 heat problems have been fixed, and they both are doing well. I think they have so much in common the differences are fairly trivial. If there was a major difference then people would just agree - like nobody argues that the Wii's graphics aren't as good because it's a simple fact.








