Cotto was surprisingly fast as the fight started. The accuracy and power of his sharp jab was frightening to say the least, and would have made for a very dangerous fight if he managed to capitalize on it. But Manny managed to adapt to Cotto's timing by the third round, and countered the most dangerous weapons the Puerto Rican brought to the fight. Pacquiao's right hook and left uppercut proved to be devastating, and send Cotto to the canvas twice in the early rounds.
For the rest of the fight, Manny dominated the ring with amazing combinations, catching Miguel with an amazing variety of power punches, coming in at every angle. Cotto's massive heart kept him going, and kept landing that sharp jab, but in the end it just wasn't enough. The referee asked him at the end of the 11th if he wanted to continue, and Miguel want to keep fighting. But in the middle of the 12th and final round, Miguel just couldn't keep up with the pace Pacquiao was setting, and the ref closed down the fight.
The Mayweather/Pacquiao fight seems closer than ever. If Floyd was watching this fight, he might be wondering if he can use his jab as well or better than Cotto against Manny. If he can push for it, I can think of no reason why this fight couldn't, shouldn't, or won't happen.