Continuity mistake: During the initial conversation when the camera is on Elaine there's a chair prominently featured in the background, with a jacket on the back. The chair turns around between shots - in particular, when Jerry proudly proclaims himself "Master Packer" it is positioned at the desk instead of facing towards the camera. (00:01:10)
Continuity mistake: George is chatting with Elaine as he is waiting for Jerry. Elaine splits an Oreo cookie. When he mentions her "price range", she is not seen fully but her left hand is in frame and she brings it up. When George turns around to address Jerry though, it's her right hand to be raised. (00:03:20)
Continuity mistake: When Jerry is making the "Lo Mein" joke inside the video store, he is waving his hands around. The hands are out of frame; still his right hand pops in view twice showing he is holding a tape - but he is holding none before and after and he positioned himself away from the shelf. (00:01:35)
Continuity mistake: Jerry is playing with his mom; she handles him a note with Elaine's message. He says "I am such a jackass." His mom asks "She knows... what?" In that shot, Liz Sheridan 's hand is nowhere near her face, where it should be to match the shots before and after. (00:16:55)
Continuity mistake: Throughout the video store scene, a golden sticker keeps switching position on the adult tape Elaine is holding; The Switch can be noticed particularly easily when they talk about the wedding; Elaine repeats "A wedding?" and the box has no sticker, but few seconds later she laughs about the combover and the sticker is showing. (00:02:50)
Continuity mistake: In the pilot episode "Good News, Bad News", look out when the waitress discusses the two coffee pots. She says "Trusts me George, nobody wants to see you on caffeine", and the unbuttoned top of Jerry's jumper is noticeably folded - but straightens instantly in his reaction shot. Also it should be noted that she walks away without actually pouring coffee to George - you have to assume a little amount of time elapsed between that reaction shot with Jerry and the following on George. (00:01:45)
Continuity mistake: When Elaine joins Jerry and George at The Cafe and tells them she spent ten minutes looking for a grape, keep an eye on the straw in George's drink. From shot to shot, the straw in George's drink keeps changing position, from tilted to upright, then tilted at The Opposite end of the glass, then upright again, then back to tilted.