What Could Have Been: This image◊ was created in case Jason Todd was voted to survive A Death in the Family. A very similar colored version (here◊) was printed in Batman Annual 25, which recounts Jason Todd's resurrection, as well as the reality-warping that caused it.
Awesome, Dear Boy: The reason several of the guest-stars took the gig as villains. Victor Buono as King Tut is the best example: he was a huge (no pun intended) fan of the comics, and was so into the series he made more appearances than any other guest-star outside of Newmar, Romero, Meredith, and Gorshin.
Fake Brit: Lord Ffogg was played by Rudy Vallee, an American born in Vermont.
Spencer Tracy was offered the role of The Penguin, but would accept only on the condition that the series got to end with him killing Batman.
Also, Two-Face was once considered as a villain for the show, only his origin would be that he was a TV news anchor who had a TV set blow up in his face. Clint Eastwood was even considered for the role but the character was ultimately dropped because he was considered "too gruesome" for such a light-hearted show.
The season 2 episode "The Puzzles Keep Coming/The Duo is Slumming" was originally written for the Riddler, but with Frank Gorshin having contract disputes with the producers, the similar Puzzler was created instead.
Creator Backlash: Tim Burton once said of the film "I liked parts of it, but the whole movie is mainly boring to me. It's OK, but it was more of a cultural phenomenon than a great movie." He also wasn't horribly enthusiastic about how Prince's songs were used in the film.
Main screenwriter Sam Hamm, one of the many writers who worked on the script, has also absolved himself from the sequence where Alfred leads Vicki to the Batcave, a move that didn't sit well with a lot of fans. Hamm said the scene didn't come from him and that the day Alfred let someone in the Batcave would be his last day of employment. It gets a Call Back in Returns.
In the original script, written by Tom Mankiewicz, crime boss Rupert Thorne hires Joe Chill to murder Thomas Wayne because he is running against Thorne for city council.
The script also has a large part of the film concentrating on Bruce traveling abroad and training with Henri Ducard. Bruce would discover Ducard to be a criminal. Ducard was dropped from the original Tim Burton film. The draft was written by Sam Hamm, the screenplay writer of the film. Hamm was eventually invited to write for Batman comics where he incorporated his character into the comics.