We will be on the Carnival Pride to the Mexican Riviera in November 06. It will just be me and my daughter and we are planning in Puerto Vallarta to go to Yelapa than come back and do some shopping and maybe the krystal resort. In Mazatlan we are going to stone island and eat at victors than comming back to town and shop in the golden zone or go to El Cid and use their facilites. In Cabo since we only have a small time in port we will walk around town a little and just go to medano beach for a while maybe take a glass bottom boat ride. There are soo many things to do just depends on how much you want to spend and what type of things you like to do.
I highly recommend an all day snorkling, scuba, kayak, whale watching (in season) and beach excursion when you visit Puerto Vallarta. There are several companies that do this. They will pick you up at the ship, with unlimited drink and food with all supplies furnished.