The song was a true Lennon/McCartney collaboration, joining two unfinished songs together to form a whole. John's One of the Beautiful People provided the pseudo-press-conference-style verses and the rousing chorus came from Paul. Though the lyrics deal with the question of fame, they do so in a lightweight, even a lighthearted, manner. This was the middle of the psychedelic era and it was the overall sound of the recording - the texture, if you will - that was paramount, and the sound they achieved on this day was impressive, indeed.
The most unique element of that sound came from a keyboard called a Clavioline, a precursor to the synthesizer. John Lennon commandeered this instrument, which was only capable of playing single notes at a time, not chords, and utilized it throughout the song in a haphazard way that somehow works to great effect. All of the other instruments - piano, guitar, drums and bass - have a clean, sharp sound. The band's usual Abbey Road Studios engineer Geoff Emerick, a true perfectionist, relates in his book Here, There and Everywhere that he admired the sonic quality of the bass in particular when he heard the finished product.
When the single All You Need Is Love required a B-side soon thereafter, this recording was chosen for that purpose and thus was withdrawn from consideration for the Yellow Submarine soundtrack. A brief snippet of the song was eventually used in the film, however. Only the introduction is heard very quietly as Ringo takes a hole out of his pocket and frees Sgt. Pepper's band from the glass bowl they have been trapped in for most of the action. The song therefore made it onto the Yellow Submarine Songtrack album released in 1999.