To promote the film, Will Ferrell assembled 1,580 of his friends and their acquaintances at a superhero costume function. This party set a Guinness World Record for the largest gathering of superheroes.
There are numerous references to Superman in this film. These include: - The way Megamind's parents put him in a capsule to Earth just before his planet is destroyed - The love interest is a reporter - Hal's "space dad" is obviously modeled after Marlon Brando as Superman (1978)'s father in Richard Donner's film version - Almost all of Metroman's super powers are the same as Superman's - Megamind's pronunciation of Metro City has the same stress pattern as 'Metropolis' in Superman - Megamind's alter ego Bernard wears glasses like Clark Kent. - In the Metro Man Museum, there's a statue of Metro Man preparing to catch an airplane. This is a reference to John Byrne's 'Superman' comics, where Superman made his first appearance by catching a plane and saving Lois Lane.
The film was originally titled "Master Mind". However, the name had already been trademarked by the makers of the 1970s board game and TV show Mastermind (1972), so it could not be used. It was then going to be titled "Oobermind", which was a misspelling of the term "über-mind." The word "über" refers to something that is large or great; in this case, the title character's over-swollen skull/brain. But it didn't sound right, so it was revised to become "Megamind".
In the office where Megamind in lamenting his destruction of Metro Man, the camera pans across the room until it stops on Megamind addressing an infamous 'Drinking Bird'. As the camera pans you can see what appears to be the Ark of the Covenant as well as what seems be the Maltese Falcon on the desk to the right of Megamind as he begins to address the Drinking Bird.
At the end when MJ's track 'Bad' was playing & Hal was dancing along it, the Warden was seen to play along with two of his guards. Their 'head shaking step' was taken from Saturday night live's "what is love" skit, which also starred Will Ferrell.
The trivia items below may give away important plot points.
In the early portion of the movie, when Megamind has Metro Man trapped in the real abandoned observatory, look closely at the scene where the images of Megamind and Metro Man are being projected upon the buildings. Just after Megamind orders Minion to fire the death beam, there is a single frame where Metro Man fades slightly from the observatory screen and reappears faintly behind Megamind on the opposite screen. This was intentional to foreshadow Metro Man's story of how he faked his death.
The dresses Roxanne wears throughout the film visualize her relationship with Megamind. When she first appears she wears a red dress, when Megamind was her enemy. Later she wears purple as she and Megamind develop a better relationship. Roxanne's final dress is blue as she has fully accepted Megamind.
Hal the cameraman is seen wearing a yellow "sad face" badge. This is a tribute to the Alan Moore comic 'Watchmen', where a superhero (The Comedian) wore a yellow "smiley face" badge. Considering that The Comedian was an unbalanced vigilante, this could foreshadow Hal's corruption and instability.
Whenever a character uses the disguise generator their eye color remains the same, such as when Megamind uses it to disguise himself as Bernard. The sole exception seems to be when Minion uses it to disguise himself as Megamind during the climax of the film.
When Metro Man fakes his own death by escaping in the last millisecond and replacing his body with a skeleton, it directly mirrors events in the major DC Comics storyline "52", which documents a full year where Superman, Batman and Wonder Woman have disappeared from the public eye and are presumed dead (similar to the events of "Megamind"). In "52", time-traveling superhero Booster Gold also fakes his own death in an identical fashion to Metro Man by replacing his body with a skeleton at the last second in order to be able to secretly reinvent himself as a different superhero, Supernova, and save the day.
During the opening of the Metro Man museum, "A Little Less Conversation" by Elvis Presley plays. This presages the later part of the film, when it is revealed that MetroMan faked his own death, grew a beard and lives in hiding, as persistent rumors claim Elvis did.
Hal Stewart is an amalgamation of various comic characters: his appearance was based on Jimmy Olsen, he was named after the Green Lantern (a title notably held by Hal Jordan and John Stewart), and his character was based on Spider-Man 3 (2007)'s Eddie Brock.
Megamind lands in a prison, where he is raised to be a criminal. This alludes to 'Superman: Red Son', a graphic novel which demonstrates what could happen if the infant Superman had crash-landed and was raised in a location other than a Kansas farm (in the story it was the Soviet Union). Both also have similar denouements: the hero retires, goes into hiding and leaves his work in the hands of his former nemesis.
Minion's suits increase in scale throughout the film: he is first seen wearing a remote-controlled suit in Megamind's childhood; he is seen throughout the film in his own robotic suit; and finally at the end of the film he is riding the giant battle suit.