No sweat Laura,
I wore my dark suit, dark gray for formal night.
Saw guys with summer tropic suits, think creame and even some guys with Kilts and browns and greens.
Of course the tuxeos were out numbered but I'm convinced that the real reason we have formal nights is two fold.
1) Cruise Lines know its the women who will decide a nice vacation away from dishes, meal preparation, kids, inlaws is needed and its time to remind the TV couch / sport jock that a suit worn out together would be romantic and its about time we did it together. Of course a cruise is the way to do it all.
2) Cruise lines know quite well, formal night is really for the woman, period. And boy do they know how to look and remind us guys why we got married in the first place and if we are single why we still look. Mind you I still look, as my wife says , as long as you bring your appetite home.