On the Voyager and Radiance class ships, approximately mid-ship, the hull bulges out into a "hump" or "bump". There are about 10 cabins on each side of the ship on the Voyager class, and the same number on the starboard side on the Radiance class. On the port side on Radiance class are the glass elevators that look out over the sea. On the upper decks there are fewer cabins on the bump, because that's where the suites are.
Is it something you should want? Hard to say. We like them because some of the balconies on these cabins are larger than a stardard balcony.
If you can get a Royal Caribbean brochure, you can get an idea of what I'm talking about.