He doesn't move as much in general, but watch the second Pacquiao fight, or against Casamayor and you will see his ability to close the gab is still incredible. The reason he had so much success agianst Pacquiao is because he could get in quick enough after Pacquiao missed his punches. Not only that but he could lead against Pacquiao and land flush which is something Barrera, Oscar De La HOya, and more impressively Ricky Hatton couldn't get even close to doing. Marquez obviously doesn't move as much as he used to, but neither does Mayweather who seems to be in love with defending himself off the ropes instead of using lateral movement.