Thank you, donaldsc, for the post. Binoculars are a fantastic addition to a cruise! I'd like to piggyback on your discussion.
Once you get over 8x magnification, binoculars will show you just how shaky your hands are! Years ago, when I started birding, I did some research on binoculars. Lots of great pairs our there, including stunning clarity from manufacturers like Swarovski. But our human inability to hold things steady over 8x means that unless you have a tripod/bipod/monopod, you won't be pleased, regardless of the lens quality (and who wants to carry extra stuff around).
There was only one solution: Canon binoculars with image stabilization.
My pair is the Canon 12x36 IS III, made in Japan. It's absolutely stunning what happens when one presses the stabilization button on top! It's so good you can use it in a moving vehicle! They are expensive (~$700) but they'll be the last pair you buy and will greatly increase the pleasure of using binoculars to pick out details. I'll never go back to unstabilized binoculars, period.
-Eric