Cash Cow Franchise: The three movies were huge financial successes. Even the third, which wasn't well-received by critics or fans, was still a success, to the point of being the highest grossing domestic release of 2007, and the highest grossing Spider-Man film worldwide to date.
Development Gag: The second film has a couple of playful jabs at Tobey Maguire's back problems, which nearly forced him to drop out. This includes the "I'm back, I'm back! ůMy back, my back!" scene, and a Freeze-Frame BonusBugle headline claiming link between back pain and brain shrinkage.
Dunst (it was a wig in the first film, but she liked the look so the sequels are literal cases). Interesting, considering Dunst is a blonde playing a redhead and Bryce Dallas Howard is a redhead playing a blonde.
Maguire, Church, and Grace all gained double-digits pounds of muscle.
Executive Meddling: Raimi had initially had no intention of using Venom since he felt the movies he was making did not have the right tone for the symbiotes, but Sony convinced him otherwise.
Whilst the game based on the first film was well received upon release, the sequel was such an improvement that it has since fallen under this trope.
The PSP version of Spider-Man 2 is widely considered to be a lackluster game, lacking most of the features that allow the home console version to avert this trope.
The Spider-Man 3 games, are a bit more complicated. Whilst the PS3/Xbox 360/PC version is considered a decent-to-average game that doesn't improve upon it's predecessor, the PS2/Wii version is considered a widely inferior game that took several steps back from Spider-Man 2.
Star-Making Role: For Tobey Maguire. It was also James Franco's first big role, but he never became a main event player until later on. Some actors and actresses in the cast also got additional boost because of the trilogy.
Jake Gyllenhaal would've taken over the role of Peter Parker if Maguire's back problems became too much. Which makes a lot of sense; they resemble each other so much, they actually played brothers in the film of the same name.
The script for the fourth film which caused Raimi to leave. According to reports, it had Peter married to Mary Jane for several years, Adrian Toomes replacing Jameson as head of the Daily Bugle, Spider-Man deliberately killing the Vulture, inciting the wrath of Felicia Hardy — who would here not be the Black Cat, but the Vulture's daughter, with whom Peter would essentially cheat on Mary Jane with; and most notably, the ending would have had Mary Jane leaving with her and Peter's baby, and "Spider-Man No More" happening again. According to sources, Raimi was repeatedly vocal about how much he hated this script.
Sam Raimi also wanted Dr. Curt Connors (who was played by Dylan Baker in the previous two films) to become The Lizard at some point in the film.
Stan Lee was going to deliver the "He stole that guy's pizza!" line in 2. An outtake of this can be seen at the end of the DVD's blooper reel.
Years ago, James Cameron was going to do the Spider-Man movie with Arnold Schwarzenegger as Dr. Octopus. During this time, there was also another R-rated treatment that had a villain who was a Composite Character of Norman Osborn and Electro, would feature Spider-Man killing criminals, and would have MJ and Spidey having sex on a big web while Peter kept his mask on.
Doc Ock doesn't become fused with his arms until the subway fight.
Doc Ock is obsessed with Spider-Man because the chip he gave him can stabilize his fusion with the bionic arms.
Aunt May would've been angrier with Peter when she finds out that he could've stopped Uncle Ben's killer. Later on, they have a discussion where feeling crushed by your responsibilities is normal, not something you can escape from, and not a special destiny.
Cat O'Conner and Kari Wahlgren replace Kirsten Dunst as Mary Jane in the first and third games respectively, with Dunst only reprising the role in the second game.
Jay Gordon and Josh Keaton replace J. K. Simmons and James Franco in the respective roles of J. Jonah Jameson and Harry Osborn, with Simmons and Franco reprising the roles for the third game. Gordon also replaced the late Randy Savage as Bone Saw McGraw.
Mindy Sterling replaces Rosemary Harris as Aunt May.
Jeff Coopwood and Charlie Robertson replace Bill Nunn as Robbie Robertson in the second and third games respectively.
Bethany Rhoades and Rachel Kimsey replaces Elizabeth Banks as Betty Brant in the second and third games, respectively.
Peter Lurie replaces Ron Perkins as Mendell Stromm. Lurie himself was replaced as Kraven by Neil Kaplan.
Dylan Baker is replaced as Curt Connors by Joe Alaskey in the second game and Nathan Carlson in the third.