In Cozumel we chose to keep our feet dry (No water based excursions).
We tried to book the Salsa and Salsa event based on internet comments.  They are in negotiations with Carnival to add them to excursion options, but the boat did not yet offer the trip.  Because they are in negotiations, they would not allow us to book directly with them. 
Plan B.  We took a cab ($7) to the Plaza so the wife could shop.  On the way there (15 minutes), it started pouring rain.  She wandered around the small shops to the East of the Plaza. We both got soaking wet (so much for keeping our feet dry).
After a couple of hours the rain stopped and we had lunch in a small restaurant/bar down an ally to the west of the Plaza.  Excellent steak fajitas for 2 for $11!
A little more shopping, cab back to the boat, and some rest before departure

Cozumel

Of all our ports, I was the most pleasantly surprised by Jamaica. (I think because of all the negative comments I had very low expectations) 
After researching attractions in Jamaica, the wife and I decided on Dunn's River Falls. I tried to book a 3rd party trip, but none of the recommended tour guides for Dunn's River travel from Montego Bay. So we were forced to book the Carnival excursion. The tour departures in Montego Bay were very disorganized.  One would think with all the practice they would have the process perfected.  They were constantly checking our tickets and tell us to get in another line.  We assumed that the line would form behind the sign listing our tour (Duh).  Our group of about 16 was herded to a bus that would seat about 24.
I sat in the passenger seat of the mid-sized underpowered bus to Ocho Rios and the falls.  The 1 3/4 hour bus trip was scary. Passing trucks on hidden curves, and at the last minute sneaking ahead of the passed truck.  Tailgating the vehicle in front by 5 foot at 50 MPH is SOP. 
The tour guide was pleasant and did a good job pointing out all the sites. After that there was a detailed history lesson on Jamaica (more than some wanted). If you want to know the shoe size of the official on the Jamaican $2 bill, you will enjoy it.
I could not hear a word of what she said since the diesel engine noise between me and the driver drowned out her speech. The falls were very crowded and the guide was not clear where we would meet after climbing the falls.  Eventually we got the group reassembled and made the 10 minute drive to the Dolphin cove beach where the Dolphin encounters are held. A hamburger was served (very bad) and we left on our own without a clear meting point or time. 
You can view the Dolphins doing their tricks in the adjacent pond, the sand beach was nice, and facilities include spring-fed showers to wash off the salt and sand.
We found the guide and asked when and where to meet. At the specified time we returned and could not locate our guide or other members of our group.  We finally located another couple and they were frantically looking for the guide (they had not been given a time or place).  We finally located the guide in another area and she led us to the bus where others were waiting.
Since this tour requires a lengthy bus ride, it provides an excellent opportunity to see most of Jamaica's south coast, and Dunn River Falls is one of those tourist attractions you have to do once. 
I downgraded my rating because of the disorganization of the tour.
And the constant begging and harassment of the vendors near the falls is irritating.

The water clarity approaching the Caymans is some of the clearest I have seen in the Caribbean.
The Caymans are much more upscale than Jamaica. And items (i.e. Booze)  cost considerably more.
I had researched the best Stingray city tour, and Moby Dick kept getting favorable comments.
I traded emails with them to reserve a spot. The outfit is run by several Englishman that obviously love what they do.  After finding their awning and signing up, we briefly walked around Grand Cayman and returned to their Awning at the specified time.  Our group of about 15 was taken to an old blue school bus for the 15-20 minute drive to the dock. (Thank goodness it had retrofitted A/C).  The bus driver was pleasant and pointed out the main sites along the way.  We boarded the boat and were fitted for snorkeling gear while another guide gave an overview of stingrays, how to hold, how to feed, how to react to their behavior.  The boat driver was quite funny in that English sort of way.  The Stingray sandbar was very crowded with cruise ship excursions so he took us to the snorkeling reef first.  It was about  mile from the Stingrays and the water depth was 7 ft. Water clarity was good (20+ ft) and one of the guides located his Pet Moray Ell for us to see and photograph. About 1 hour later we were off to Stingray City.  
There were fewer boats now, and the guides Herded 15-20 rays for our group.  The guides made sure that everyone handled, fed, and kissed the rays if they wished.  The rays are intimidating at first because they rub and massage your body.  After swimming with them for 30 minutes you get used to them and their antics.  
On the way back one of the guides unexpectedly dove in the water from the moving boat to retrieve a starfish for the guests to hold and photograph before returning it to the water.  
We also had a Dolphin escort for about 15 minutes of our return to the dock.
I strongly recommend the Stingray tour, and specifically Moby Dick tours ($45)
They went all out to make sure all the guests had a great time.
Before returning to the ship, we walked around the port city for a couple of hours.

The location was convenient for dining, Lounge deck (5)and access to the lido deck. Downside: A slight elevator noise at night.

Balcony was nice.

30 minutes later, the Cruise director announced that our ship had been released from the search and we were free to resume our return trip.The cruise director came on the intercom at 7:15 and announced there was a person lost overboard and the ship was assisting in the search.

Carnival Conquest Review

Disastrous ending to an otherwise decent cruise

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