For me 2 things I have a problem with -
1. Paying for the right to play online - I find it insulting to have to pay for online gaming unless it's an MMO. I have gotten accustomed to playing online for free on my PC and ps3.
2. Reliability- Am still worried about RROD and problems with the DVD drive.
Without those 2 things I would already have been a 360 owner. Even though I prefer Sony I did love my xbox last gen.