While there hasn't been an official announcement yet, I just read an article tonight that claimed all signs point to a May 2nd fight between the two. Of course, I guess that means nothing until the contracts are signed.
Personally, I think it's a lose-lose for Mayweather at this point. If he loses, well, he's no longer undefeated. If he wins, then he beat a fighter who's definitely past his prime. That being said, I'll still shell out my money to see it on PPV.