we did the KonTiki Rum raft on St. Thomas. You get it right at the pier, and tour around the point in a glass bottomed boat, and the rum you can drink and all the steel drum band music you can tolerate It was cheap and a really good time. It stops around the point for a swim and drink on a small beach with only us there.
Shopping is a must on St. Maarten!!!! And we love Cupecoy Beach (nude beach with sandstone cliffs and private grottos for sunbathing)
We are going on the Triumph too, but not until New Years. Have a great time, and post here when you get back.
St. Thomas - Our group went on Godfrey's Tour; we shopped, had the option to snorkel, and went on a tour all for a cheap price. My only regret was I opted not to snorkel.
St. Martin - We went on the See & Sea Tour. I thougth it was fun. We had a tour of the island, went out on a glass bottom boat, and climbed to Fort Louie. (I thought I was going to die before I got to the top). Much to my suprise, I am not in as good of physical shape as I thought I was. If you are in good shape, the view from the top of the Fort is awesome.
You can also walk from the port for free and shop. Most of the shop owners will negotiate with you on price (except Cartier).
We went to St. John and we went to Cinnimon Bay and then went wave riding and had a good time. That was a god beach that you didn't have to pay for and they had a surf/water toy rental building. The Triumph is a very very nice ship you'll like her.