There were only a handful of tuxedos on formal night, not many dress up anymore, lots of men with sports jackets and shirts (no ties) women even wore trousers and tops. Its gone very informal, we dressed up both nights, but not in tuxedos and big ball gowns just a shirt and tie and a nice dress for me! If its your first cruise its nice to get a picture taken in a tux but otherwise dont go to the expense of it. The lobster night was the Thursday night of the cruise. The first formal night is Sunday and the second one Thursday (im nearly sure) as for dancing and singing yes! All that throwing the napkin in the air and whizzing it around zzz lol!!!