A better headset, Kinect, better hdmi cables, hdmi in, more apps, free Live, ext power supply may be more worth than a slightly better gpu to those who care about those things... but if you value better performance then all these things have no value at all.
I think it all depends on your preferences. I like Xbox exclusives way more than Playstation exclusives (I'm not a single player centric gamer) and I also like Kinect and party games as I have a lot of people to play these games with. I don't care for tv integration but what MS offers to a gamer like me is better value than Sony's offer.