Colbert Bump: Guy-Manuel de Homem-Christo and Thomas Bangalter of Daft Punk are huge fans, and even fulfilled a lifelong dream of theirs by collaborating with Paul Williams on the album Get Lucky, thus raising public awareness of the film significantly and helping to introduce a new generation to it.
Could've been even worse if they hadn't changed the name of the character from early scripts; Swan was initially meant to be called "Spectre". (Given that Spector's instability was well-established amongst the recording industry at that point, it was most likely intended as a Take That!.)
Germans Love David Hasselhoff: The movie has an intense fanbase in not only Paris, but also, surprisingly, in Winnipeg, Manitoba, to the point that an annual "Phantompalooza" convention was created.
Furthermore, it played for 62 WEEKS STRAIGHT there when it first came out!
Hilarious in Hindsight: Swan programming Winslow a new voice almost becomes funny in an era full of auto-tune and heavily processed vocals that sound synthetic.
Hollywood Tone-Deaf : The female singers who audition are intentionally bad, to make Phoenix look better by contrast. By the third audition scene, when Swan is seeking his "new sound," they're all pretty good, just bland.
Moral Event Horizon: Subverted. Judging by the tape, Swan in 1953 seemed like a very narcissistic and egotistical hedonist but ultimately not a monster, and had been producing gold records (presumably not stolen ones) since age 14. At some point after his Deal with the Devil, he obviously became the horrifying thief and abuser we see him as, though nothing in the deal itself said he had to. Alternatively he could've been that way all along, and we just didn't see it.
He openly states to Philbin that he abhors perfection in anybody but himself; he was very vain to begin with, wanting to commit suicide because he didn't want to grow old and lose his good looks; when the devil asks him if eternal youth is worth his soul he replies "What soul?". Swan was a complete monster all along. He's not above using people to get what he wants, and everybody is a tool for him to use and abuse.
For the first hour of the movie anything Winslow did was at least understandable. But when Phoenix's performance is about to start he murders the totally innocent stagehand operating the spotlight so he can man it— and he murders Beef for no better reason than he was in the wrong place at the wrong time— showing how far he has gone in his anger and obsession.
Retroactive Recognition: For the Whose Line? fans, there's Archie Hahn as one of The Juicy Fruits. In fact, it's a little strange watching him in this film, and actually sing really well, while on Whose Line?, he... well.... didn't.