(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.
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 when Ann and Jack are walking back to her apartment above the video store, you can see a storefront whose marquee says the address is on Ann Street. The Video Spot T-shirts proclaims the store to be on Duane Street.
After the double-date dinner at the Chinese restaurant, Anne unlocks the door to the apartment and puts her keys in her purse. The next scene, she is hugging Jack and you can clearly see the keys still in her hand.
The recording of Jack's diatribe on yuppies is very different from the "live" version we saw earlier.
Parry blinks when Jack is yelling at him in the hospital. If Parry is catatonic he shouldn'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.