Parry has a bruise on his forehead for most of the movie. When he is in the hospital, it and his other injuries are gone. In the last scene, in Central Park, the bruise is back.
After the double-date dinner at the Chinese restaurant, Anne unlocks the door to the apartment and puts her keys in her purse. Then she is hugging Jack, and the keys are still in her hand.
The recording of Jack's diatribe on yuppies is different from the "live" version seen earlier.
(at around 1 min) When Jack is talking to Parry in the basement, Pinocchio's head (on left) changes position three times each time the scene cuts back to Jack.
After the double-date dinner when Ann and Jack are walking back to her apartment above the video store, a storefront marquee says the address is on Ann Street. The Video Spot T-shirts proclaim the store to be on Duane Street.
Parry blinks when Jack is yelling at him in the hospital. If Parry is catatonic, he couldn't be able to blink.
After the little quarrel with Anne, Jack gets a call. When he picks up the phone, it still keeps ringing for a short moment.
When Parry is in the hospital and Jack comes to visit him, Jack approaches the bed. To the right of the frame is a man wearing shorts with a walkie talkie clipped to them.