Continuity mistake: When Frasier and Roz are in the cafe talking about the See Bees, Roz says something like "Those shows are torture." When she does there are many different shots in a short space of time and if you're quick you can see the coffee mug suddenly jump into her hand without picking it up.
Character mistake: Frasier tells Niles that the article on him will be in the winter/spring issue of Seattle Broadcaster. The man who interviews him introduces himself as a journalist from the Seattle Times.
Answer: Nanny G (Nanette Guzman - played by Laurie Metcaf) has been a children's entertainer for twenty years, and tells Frasier, "Do you know what it's like to play the same character for 20 years?!" The joke is that Kelsey Grammer has been playing Frasier Crane since 1984, when the character first appeared on "Cheers", so Kelsey in real life has been doing just that!
Super Grover ★