I just got back, last weekend anyway... I did the helmet dive in Grand Turk and really enjoyed it. The Barefoot Sail Away and Snorkel in St. Thomas was a lot of fun. And yes it was a barefoot sail away, they took our shoes when we got on the boat and returned them at the end. Also the Rain Forest in San Juan was very nice.
The only one I thought was a bit of a disappointment was the glass bottom boat in Half Moon Cay. That was my second choice since the snorkeling was sold out.