When Aria, Mike, and Mona go to the theater, they are attending a screening of Strangers on a Train (1951). However, when the film begins playing, Max Steiner's 1937 Warner Bros. fanfare from Tovarich, Casablanca, and the Maltese Falcon plays. This fanfare does not ever play during the actual movie; instead the film's score by Dimitri Tiomkin plays over the Warner logo.
Near the beginning, when Spencer & Emily are chatting over coffee, the amount of whipped cream in Spencer's mug drops then rises again between shots.