If Cotto loses all it means that when he fought a true elite he lost. I'm not sure if Shane is at the high end or low end of the elite considering his age and 4 or 5 losses (depending on who you talk) but nevertheless he is elite and it will be Cotto's entrance to super stardom if he wins. But if he loses, and loses because descisively he will be looked at as a good PR fighter who can beat the B's ala Gatti, and Vargas later in his career.
when anyone says that if a fighter looses to another at this level it's bull****. And most people who say so are morons like bigtime and unbeatablefloyd.
Cotto has the tools to give Mayweather all he can handle - not saying he would win, but it wouldn't be a cake walk by any means for Floyd.