If you're just going on this cruise where you might need the telephoto, then a 55-200mm might be enough and you could save some cash there.
However, long term if you're thinking of wanting to get closer to the action so to speak, use your feet, or invest a little more in the 55-300mm or 70-300mm instead.
I have the 55-200mm and there have been times I wished I had spent money on the 55-30mm instead, but immediately after I've thrown that thought out the window and just stepped up closer, or lived with the 200mm shot. I was looking at my collection of pictures yesterday, and I can honestly say, there are very few pictures that I've had to go near the 200mm end of the zoom, so glad I saved a little and never bought the 55-300mm.
I have used the older 18-200mm and it is a very nice lens, and certainly for my amateur eyes, the pics were great. The only thing to watch on it is the lens creep (which has been fixed in the new VRII version).