The 116-112 scorecard is a bit hard to swallow. Manny maybe won it by 115-113, draw-draw... but if he hadn't gone all aggro at the end of the fight, he would have lost it.
In the end... he did just enough... landed more power punches. Landed more shots. But Marquez seemed more effective in the middle of the fight.
The booing for Manny is because Marquez sold his punches better. Threw more combos (though they didn't all hit) and his power punches seemed to shake Manny more. But in the end, Manny won by the numbers, even though Marquez had more style and technique.
Unsatisfying. Should have ended in someone getting knocked down. Conspiracy theorists have it that Manny was playing soft to entice Mayweather to come out and fight him... personally, I think that it's a case of Marquez just doing a bang-up job in the ring.