We stayed there in the summer of '02, and did a day visit on a cruise stop a year later. It was a lot of fun, and there is always something to do--it is a very busy and active place! The pools are great, there are a lot of designer shops, The Dig is very interesting, and all the sea life (stingray pools, etc...) is so neat! As long as you're prepared for the sticker shock when you see some of the prices as others have mentioned--dh, ds (then 6) and I paid over $100 for lunch at a pizza buffet (note to self: check prices *before* you go)! I loved looking at all the HUGE private yachts in the harbor--we saw Puff Daddy's, and I swear it was bigger than our house.
I'm not sure we'd ever go back for a land vacation there again, as we tend to like places that aren't as crowded, but we did have a really great time!
Have fun!