Lee is 23 years old. In the pilot episode Melissa said she was 31, which would supposedly make her 33 in this one.
Melissa's middle name is Jo.
Footage from this episode used in the season four opening credit sequence includes a shot of Michael passing a plate of food to Nancy and Gary.
Melissa's fantasy where she imagines herself as opposing boxers in the ring was patterned after the look of Martin Scorsese's modern film classic Raging Bull. Shot in black & white, Melissa imagined herself as "The Judge" and "The Kid." She debated with herself about her relationship with Lee as she gave herself a beating. Michael was the ring announcer, Ellyn was in her corner, Elliot was the fight broadcaster and Russell sat watching in the audience. Another fantasy scene had Melissa imagining Lee acting like a childish brat during the Steadmans' dinner party.
When this episode originally aired, a great controversy erupted over the scene showing Russell and Peter (David Marshall Grant, Peter Frechette) in bed together. Some sponsors backed out of advertising on the broadcast, others threatened to, several conservative and/or religious groups condemned the show, boycotts were talked about, etc. The scene showed the two men bare-chested sitting up in bed after apparently spending the night together, talking about being gay, how far "out" they were, and the current AIDS epidemic.
Michael: Tuesday night, our house, you'll come over to supper, then we'll watch Harold and Maude.
Harold and Maude (1971), starring Ruth Gordon and Bud Cort and directed by Hal Ashby, was a film about the very odd relationship between a young man and a much, much older woman. Michael is obviously using the reference here simply to needle Melissa, but it does point up her overriding concern that her friends will not approve of her relationship with a younger man.