Chris, I am going to be fishing 1 or 2 days in Cozumel on my trip this 16th - 21st with
http://www.fishingcozumel.net/rates.htm .
They do trips out of Playa del Carmen as well and will let you know how they fared. All the reviews I saw online from tripadviser were mostly great. All the bad ones seem to be people that were complaining of fishing and not catching.