The PS3 has more space, power, and the ability to play blu-ray disks, allowing it to play bigger games. It also doesn't have an annual failure rate of 20%.
The xbox360 has more titles, hordes of bad players, and... alright I ran out of ideas.
The only reason I have an xbox is because the PS3 still costed $600 at the time.
All physical problems can be solved with high explosives