When Linda decides to come downstairs to join the New Year's Eve party, her hairstyle when she begins her descent changes as she is descending the stairs.
After Johnny and Linda do their acrobatic trick and they are sitting on the floor, the next shot shows them sitting closer together than they were before.
The amount eaten from the apple varies between shots when Johnny is in the playroom with the bitten apple in his hand.
When Johnny and Linda start waltzing, they are quite close to each other. However, in the next shot there's a larger distance between the two.
Though it's the Christmas season and everyone on the sidewalk is wearing overcoats, the cab driver in the opening scenes has his driver's side window and one of the back side windows cranked open.
However, this is not a goof as it can be explained by several scenarios, such as the cab's heater won't shut off, the cabby always feels hot, or there is an offensive odor in the cab.
At the beginning when Johnny arrives to visit the Potters, he walks down the hallway, turns the corner, and goes to their apartment door. When the door is opened, it reveals a large apartment that would extend well into the hallway and seems to have windows that would look into the hallway, too.
Near the end, as Johnny is being announced and is coming up the stairs and Neddie is trying to persuade Linda not to give up, Neddie walks away with his right arm fully extended down, forgetting that he is supposed to be carrying a drink. A second later, he remembers it and bends his right elbow at 90 degrees, keeping it bent.
Just after Nick Potter and his wife leave the elevator, moments before meeting Linda in the play room, he says: "Seems to have been some sort of residence at one time." However, his mouth does not move.
(at around 27 mins) As Johnny and Ned leave the playroom, a focused shadow of the mike boom crosses Ned's face.
The boom's shadow is visible in the playroom when they talk about Linda's artwork.