This company offers cruises specifically for motorcyclists. It sounds pretty good for a non-threatening adventure vacation. I wish they had a cruise to Alaska, but I fear I'm just going to have to take a month off sometime and ride up there on my own, for a somewhat more threatening adventure vacation.
I'm sure the guided rides are a good thing, but they sound kind of boring. That's just me, though. When I ride, I focus on riding, not looking around at the pretty pretty scenery. I appreciate riding through beautiful places, but I don't linger long, if you know what I mean.
All the same, I imagine these are a pretty good time for those of us who want to see the Caribbean by boat and wear garish shirts, but don't want to leave our bikes at home.