The port area is nice and has some different shops then what you always see. The cab drivers and vendors are a little more aggressive then in some of the ports but not to the point of being annoying.
Our tour left on time and we had a drive through Charlotte Amalie, it was nice to see the town and the guide told us the political history of the island. Our tour was a good time, we rode the Rhino rider boats about 40 minutes out to "Happy Beach" snorkeled about 30-45 minutes then back to the dock for our bus back to the ship. The excursion did get us back to port about an hour later then scheduled.
If you are in St. Thomas for shopping you may want to avoid cruises that get to port on Sunday as when we got off the boat most shops were closed. We did find a nice place for lunch after our dive and then headed back to the boat.