in mosley's defense regarding his last fight it's hard to look good against a bigger awkward guy who was completely unwilling to engage in a fight.
As for Mayweather, Floyd is simply the superior boxer to Mosley. Mosley was twitching away confused as hell as to what to do. I disagree with HERSEY on that point I don't think Mosley ran out of gas after the second I thought Floyd did a tremendous job making the proper adjustments, keeping the perfect amount of distance, got shanes timing down and countered him for the rest of the fight, thus making shane second guess himself the entire night (which resulting in shane twitching away for 10 rounds as floyd fiented, etc.).
There is a little risk on pac's part I suppose just based on styles, I mean mosley did nearly drop floyd and pac is an offensive fighter so shane will most definitely have his chances and probably more chances than he did against a defensive wizard like mayweather.
I still prefer marquez or berto of course, but I don't think it's terrible fight for pac's first fight of 2011, would be a PERFECT set up for a Mayweather fight especially if Pac could knock shane out. And if floyd is still not available, maybe andre berto can get a big win under his belt and Pac vs Berto at the end of the year.