Well, first of all, let me say that I was not in the best frame of mind when I visited this island. I had just gone through a nasty breakup and needed to get away. So I may not have the most optimistic view of this location.
I did not like the Bahamas.
I found the downtown core dirty, poverty striken (more than I expected), and dangerous. I would not walk alone in this area after dark. Frankly, it reminded me of an area of my home-city that is the home of drug addiction centers and prostitutes. Not exactly what I'm looking for in a vacation spot.
I found the locals not very friendly or helpful. They couldn't tell me where to eat, how to get around, or where to find groceries unless there was something in it for them.
I did not find the beaches to be nice - public beaches were dirty, smelled like diesel fuel from all the jetski operators, and you were hounded by vendors from the time you sat down until the time you left. One exception - the beach belonging to Radisson at Cable Beach was great - and the hotel didn't mind that I wasn't staying there. Great set up!! Restaurant, bar, and lots of chairs. Wonderful, and wonderful staff!!
The scuba diving on Nassau is great - much better than I expected. There are reefs, walls, wrecks, blue holes, and sharks!! And it is priced very reasonably, compared to other vacation locations.
Most of my time was spent underwater. I dove 5 out of 7 days. That usually left afternoons open, where I tried to hit the beach, take a walking tour (unsuccessfully), or gawk around Paradise Island and Atlantis.
So, overall, would I go to Nassau again? Not likely!! But if I did, it would be to dive and I would stay at the South Ocean Resort so I didn't have to deal with the rest of Nassau.
You can see more photos at http://www.pbase.com/kiml/bahamas__underwater