Both Paquiao and Cotto have improved, Cotto has perfected his left jab its just awesome now, and his footwork, defense have also improved. While Pacquiao has improved his movement, footwork and angles, and now is deadly with both hands. Both are furious in the ring but who do you think is all around the better boxer ATM.
Cotto by far! Its a shame that people only see Cotto as a pressure fighter, if you look back at the majority of his early fights he has excellent boxing ability and counter punching ability:yep
I am going out on a limb here and saying that pacman has the better boxing ability. Manny's competition was FAR, FAR, FAR better than Cotto has or will have. Based on that and his victories is why i am going with pacman. If cotto fought what manny fought, you would have seen a limited cotto.