I went in Sept. of 03 for our Honeymoon, and visited in 04 when we where there staying at the Spa Palace (WIFE'S CHOICE!) It is a very big place, they have bikes you can ride from your room to the various places in the resort, or you wait for the golf cart trolley type thing to drive you there. The food was great, if you go there get the Mayan Coffee, good stuff. I over-used the room service, our house maid person was so tired of bringing my drunk a$$ BLT's at 3am, that's for sure! It is a quieter place for nightlife though, but a trolley to one of the other resorts or the city will take you to any of that. The on-site snorkeling is nothing special, but you do see a lot of fish. In the center of the resort is a brackish pond/lake that you can go snorkeling in or kayaking. The closest city, Playa del Carmen is about a 20 minute cab ride, and is pretty interesting. Yummm 1 dollar Corona!! You can take a fairy over to Cozumel for pretty cheap also. While there we took a cab to Tulum, the only Mayan ruin on the ocean, went swimming with dolphins, the 2 scuba trips, and a snorkel trip...all the vacations since then have had a hard time living up to that one...we did meet some great people there though, and that always helps.
Patrick
Also, I agree with Joel, St Thomas and St John wher both very nice, all though more $$$...I visited them a few times on cruises.