Hoagy Carmichael was the first "guest star" to have a voice in an episode. And they kept his whole name throughout the show.
ABC originally broadcast this episode in black and white.
The first time Daws Butler temporarily takes over for Mel Blanc as the voice of Barney Rubble (while he recovered from a serious car accident) in 5 shows from 1961.
According to the liner notes of the long out-of-print album "The Flintstones: Modern Stone-Age Melodies", William Hanna's favorite musical moment of the series is Fred mangling the lyrics to Hoagy Carmichael's "Stardust".
The club MC who introduces Hoagy Carmichael is a parody of Lawrence Welk.