The reason Mia Farrow wears sunglasses most of the film is that Woody Allen did not feel she could pass herself as a tough Italian "broad", so he had her wear the sunglasses most of the film to hide her eyes, making her seem more sultry and mysterious.
The movie makes mention of Weinstein's Majestic Bungalow Colony resort in the Catskills (Catskill Mountains). This is where Woody Allen got his start in show-business performing magic tricks at sixteen years of age.
Woody Allen's manager and producer, Jack Rollins, was the inspiration for the Danny Rose character. Rollins appears in the movie as himself.
Etta Rollins: The mother of Woody Allen's agent-producer Jack Rollins as a balloon bender and folder in the balloon act. The movie was her only ever appearance in a filmed production.