Hitless Hit Album: Upon release, it had no singles issued (though "Strawberry Fields Forever"/"Penny Lane" were intended to be there, and the title track was a single in the 1970s).
No Export for You: The U.S. version of the original LP does not contain the infamous inner groove. It was only later restored on the later CD release, and it was included on on the 1980 U.S.-exclusive version of the Rarities compilation album.
Throw It In: The alarm clock in "A Day in the Life" was originally just marking when it would change, but it fit well as the first lyric that follows is "Woke up, fell out of bed..."
What Could Have Been: "Strawberry Fields Forever" and "Penny Lane" were recorded during the sessions for this album with the intention of them being part of it, but they ended up being released as non-album singles instead. Additionally, there was supposed to be a television special based on the album, but it was scrapped before completion. There was, however, a promotional video produced for "A Day in the Life" (as well as the aforementioned singles).
"Only A Northern Song" was briefly considered, too.
A sequel was also considered at one time, which would have featured "Baby, You're A Rich Man" (or at least its prototype, "One Of The Beautiful People")
The cover would originally also contain images of Adolf Hitler, Jesus Christ, Mahatma Gandhi and actor Leo Gorcey. The idea to put Hitler and Jesus there came from Lennon, who wanted to provoke. Eventually they were dropped because their images would certainly offend people, especially since Lennon had already hit controversy when his 1966 quote that "The Beatles are more popular than Jesus" was taken out of context. Gandhi was dropped under pressure of EMI, who feared a backlash in India where Gandhi's status is practically divine. And Gorcey was airbrushed out because he was the only celebrity who wanted a fee for appearing on the cover.
The liner notes for the 2009 release reveal the original track order for Side A was different aside from the first two (“Being For the Benefit Of Mr. Kite”> “Fixing A Hole”> “Lucy In The Sky With Diamonds”> “Getting Better”> “She’s Leaving Home"). The extreme tonal shifts when they trying to listen that way (not to mention the Downer Ending) makes for a weird experience.
Breakaway Pop Hit: The film versions of "Got to Get You Into My Life" and "Come Together" were hits for their performers and still turn up on oldies (and, for the latter, classic rock) radio.
Star-Derailing Role: Many of the musicians involved hit career slumps or derailment in the wake of this movie's failure. The only person whose career wasn't killed/nearly killed/affected whatsoever was Steve Martin, who was so popular at the time as a standup comedian that even the poor reception of this couldn't kill his film career before it started. George Burns and Donald Pleasence also managed to get off relatively lightly, mostly because they had other big hits at the same time (Oh, God! and Halloween (1978) respectively)
What Could Have Been: Supposedly KISS was approached to play Future Villain Band, but they turned it down. (Given the recent flop of their own movie, KISS Meets the Phantom of the Park, it's not surprising.)