If I were Mayweather I would want Cotto v Williams to happen then fight the winner. If PBF beats Cotto then people will say he needs to fight Williams. If PBF beats Williams people would say he still needs to fight Cotto.

Who ever wins would then have claim to beating 2 dangerous opponents i.e. Cotto (Moseley and Williams), Williams (Margarito and Cotto).

Hopefully PBF v Cotto/Williams winner will be Dec 08.