When loading to play a game it's like only 2 seconds slower than xbox. When simulating a week or a season, xbox is like 10x faster than ps2. I timed saving dynasty at the end of your game, xbox was 12 seconds while ps2 was 40 seconds.
But just to load a game and play ps2 doens't do that bad a job. Simming is a different story.
added : also the person is right that the xbox version plays a little faster than the ps2 version. It's simliar to madden on the xbox vs ps2 last year.