Cruises *typically* stop in Grand Turk. Its an impoverished island without running water. Beaches are so-so (for the carribean). Not much to see and do. I have been there twice on cruises, and am going back there this sping...and i am looking for something to do off the island (i.e. snorkel, fish, etc.) because I am done with the island.
I dont think the rest of turks and caicos is like that. I have heard good things, but Grand Turk...eh.