In the opening credits, the funnels of the inbound luxury liner Mayflower sport the white, green and red of the Italian Line. Once docked, the camera pan across the Mayflower's superstructure shows the forward funnel painted completely in red. On departure, the ship's livery is back to that of the Italian Line, and the Mayflower's bow bears the real-life name of a crack pre-war Italian liner, the Conte di Savoia.
Before Polly Bradford (Jane Powell) sings the Peanut Vendor song, the maraca player in the band's front row stands up twice and adjusts his costume both times.
(at around 1h 5m) After Denis calls Polly "just a little showoff," Polly's response doesn't sync with the spoken words. Her voice says "you're nothing but a big know-it-all," but her mouth says "nincompoop" instead of "know-it-all." The dubbed term is far less derogatory.
At about 0:02:43 when Captain Bradford enters the girls' school and is greeted by the maid the mic boom shadow moves over them, then as the camera moves in on George Brent the camera rig shadow can be seen as well.