Continuity: In Lucy's room in her parents' apartment, Barry unbuttons the top few buttons of his shirt. In the next shot they're all buttoned again.
Continuity: The cab that Lucy rides with the orange tree changes in one shot to the cab she rides later in the movie (note the cab number on the roof).
Revealing mistakes: In the scene on the boat where Luke pulls from the sea a fish that has supposedly just been caught, the fish dangles absolutely lifeless on the end of the line as opposed to violently flapping as it should.
Continuity: When Barry and Lucy are talking by the bar at the karaoke club, Lucy's hair is behind her ear/covering her ear between shots.
Continuity: In the cab ride, Jo is riding in the middle, but she climbs out last, behind both women.
Continuity: When Doug is proposing a toast, Lucy is holding her glass, but after a cut the glass is standing on the table and Lucy reaches for it.
Continuity: When Lucy and Luke are riding in Luke's car right after he picks her up, Lucy's hair is blowing straight back when the scene is shot from the front of the car showing them talking. In the shots of just Lucy from side inside the car, her hair is not blowing at all.