Errors in geography: Linus is shown looking at a fishing village (Menemsha) on Martha's Vineyard through a camera lens. He pans across until he comes to a lighthouse. There is no lighthouse in Menemsha. The lighthouse shown is in Edgartown, clear on the other side of the island (20 miles away).
Continuity: David puts olives in the martinis twice
Revealing mistakes: When David is "discussing" his engagement to Elizabeth with Linus in Linus' office, the newspaper moves around on the desk between cuts.
Continuity: In one scene, Linus and Maude are talking while Maude is riding a stationary bike. When she stops, she keeps her hands on the handles with one handle farther forward than the other. As the camera angles switch back and forth, so does the hand which is forward.
Continuity: Towards the end of the movie, Linus is stuck in traffic and must run to the E60th St. Heliport. He is shown running from the car without his bag, yet he has it when he boards the Helicopter.
Continuity: When David is confronting Linus in his office, David enters, Ron and Ron leave, David slams the door. When he does this Linus leans back in his chair. The camera pans back to David for a line and then returns to Linus who is still leaning forward at his desk, not having had time to get back to that position
Factual errors: On the third evening after the accident, David says "the stitches are coming off tomorrow". Removing stitches so quickly is not realistic.