Continuity mistake: In one scene Jim and Amanda run into each other and Amanda gets knocked down onto the pavement. She also drops the coffee, which starts to spill pretty close to here head and almost reaches her hair. In the next shot, both the spilled coffee and the cup are farther away from her head.
Continuity mistake: As Amanda leaves the party at Jim's apartment, she spots Jim sitting on the stairs. He is not wearing his tuxedo jacket; it is not visible on his lap, over the railing, etc. After the shot switches from the roommates framed in the window back to the couple, Amanda is now wearing Jim's jacket over her shoulders. It is obvious moments later when she returns it to him at his request.