Continuity mistake: As Shawn and Gus enter the office where Juliet, Carlton, and Chief Vic are sitting at the table, Carlton puts the case file he is holding on the table. Two shots later he is holding the file again, and for the next few shots his hands keep changing position without time for him to move them.
Continuity mistake: Just before Gus is awoken by noises in his apartment, there is a shot of his alarm clock. The time shows 6:07PM. When he gets out of bed, the clock says 7:01 (cannot determine if it is AM or PM). Even assuming he just lay in bed for an extra hour, he then tracks down Lassie who is about to eat lunch.
Continuity mistake: When the bank robber enters the mausoleum, his hands are empty. When Raylene points her gun at everyone, he raises empty hands. After Lassie and Juliet arrest David and Raylene, the bank robber is holding a slushie cup.
Continuity mistake: When Shawn and Gus are back at the office after the sorority ghost sighting, Gus talks to Sean from his desk. Shawn is just on Gus' right and Gus' head is turned slightly towards him. The camera angle changes and Gus is turned left (Shawn has not moved). Then Gus is again looking left.
Continuity mistake: When Shawn sees the box with the dead doctor's files, Regina Kane's file is visible halfway back in the box. He then tells Gus, "All we have to do is find Regina's." (Which he was looking straight at, but let's call that a character mistake.) A few moments later, we cut back to Shawn and Gus and Shawn finds her file in the front of the box.