When Evan brings Gladys home they do not have hats on and she lets herself out of the car, yet when she looks at Pete's film, they both have hats on and Evan comes around and lets her out of the car.
In Pete's home movie, Evan is filmed driving towards him in the middle of the street, but when Evan actually arrived, Pete was down some steps next to the building, unaware of the Jaguar's approach and not even filming.
When Gladys is posing with the plane named after her, the positions of the service personnel standing around her change between shots.
When Evan picks up Gladys for the first time, they are supposed to be going out to dinner, but as they drive round and round Columbus Circle, it is evident via the shadows that it is noon ... the shadow is under the car and under the people walking down the street. In the evening cars and people cast long shadows.
The fictional New York TV station on which Gladys appears has call letters KXIW. Call letters for radio and television stations located east of the Mississippi River normally begin with W; Ks are generally assigned only west of the Mississippi. This has been the case since 1923; however, numerous W's west of the Mississippi, and K's east of the Mississippi, have been "grandfathered." Examples are KDKA, Pittsburgh, WBAP, Fort Worth, WDAY, Fargo and WDAZ, Devils Lake.
When Gladys first sees the Columbus Circle billboard, she's wearing a dark shirtwaist dress with a white collar. When she enters the advertising agency building she's wearing a print dress. Later, out on the street, she's back in the first dress.
However it is obviously a day or so after she sees the billboard that she goes to the agency and it would take a day or so to put the billboard up, explaining the change in dress.
When Gladys goes on "The People Speak" and is obviously reading from cue cards, she breaks the word "getting" into two halves, as if the word wrapped: "get-" ending one line and "ting" starting the next, but when the cue card is shown a moment later, "getting" is in the middle of a line, not wrapped.
When Gladys pulls down the shades to watch the movie, it's obvious that lights are being turned off, off screen, instead of just the shades being pulled down to darken the room.
Pete's movie for Gladys starts with a spelling error: 'good-by' instead of good-bye.