Be aware that there is a big difference between "Swim with the Dolphins" and the "Dolphin Encounter" in Nassau. Cruise ships book the encounter, which means that you stand on a platform in waist deep water while a dolphin whisks by to kiss you. Not worth $92, in my opinion. You can book a "swim with the dolphins" on your own (same company and location the cruise ships use) for a little bit more money ($145). Check out www.dolphinswims.com
for more details about both.