It is implied George's girlfriend made him join her book club. Jessica Hecht is then shown next to George with the group. The credits show her character's name is Marie. But in the next episode Jessica Hechts' character is referred to and credited as Lindsay.
The version of "Moon River" that plays in the video that George, Joe and Remy are watching is not in the movie.
George tells the book club that Holly Golightly hooks up with "Fred". Fred is not the name used by George Peppard in the film version of Breakfast at Tiffany's. In the movie his name is Paul.
The wet spot on Jerry's (Jerry Seinfeld) couch is there before Poppie (Reni Santoni) sits down. It's covered by newspapers and as Poppie sits, he swiftly moves them aside, ready to be seen when he stands up again.
Elaine (Julia Louis-Dreyfus) states that she enjoys eating duck but in episode 9.10, The Strike (1997), claims to only eat fish.