FIFA 07 is much much much better than last year's. I think it's worth at least renting if you're a FIFA hater just to see how the gameplay has improved. Last year you could be playing with Ronaldinho or Peter Crouch and not notice any difference between the two. The 07 gameplay is so much more diverse between set pieces, the new passing, dribbling tricks, tactics, more ability to do different shots, etc. If you have Beckham on free kicks you have a better chance of scoring, if you're Gabby Agbonlahor some slow centerback isn't going to run you down on a break away. Basically the players skills are noticeable and closer to what you'd expect.
My one concern is that in manager mode the results not involving your club seem to be unrealistic this year. I played a season with Villa and I was fighting with Watford to win the league. The usual contenders like Chelsea, Man Utd were mid table. Then when I would play them Chelsea/Man Utd would be very tough to beat and I would thrash Watford.
I laughed out loud when Peter Crouch scored and did his robot dance.