Because of the controversy over gay marriage in the United States, this episode had a Parental Discretion Advised warning before the show, the first (and so far, only) time for The Simpsons. The episode was also rated TV-14 for suggestive dialogue (D) and sexual situations (S).
In Australia, this episode was rated an M and included a "parental advisory: adult themes" warning.
It is revealed that Disco Stu is Selma's fourth ex-husband.
At the end Lisa points out that Homer's marriage business is now over, with Bart questioning why. This is a reference to every harebrained scheme Homer had concocted in the past only to have it end for one reason or another. Whereas Bart's "Why?" points out that nothing really got Homer to put an end to his business even though nothing bad happened to make Homer end it. Yet in the episode after he is back working at the Nuclear Plant.
The title is a reference to the film There's Something About Mary.
The couch gag is a reference to the NHL hockey lockout of 2004, which shut down the entire 2004-05 NHL season.
Veronica sings a couple lines of the Aerosmith song "Dude (Looks Like a Lady)".
Blinky turns into the monster from the movie 'Creature from the Black Lagoon'.
After Barney takes the beer he says "as the Roadrunner says to the coyote, meep, meep!".
Howell Huser is a parody of long time public access host of "California's Gold", Huell Howser.
The song playing in the background as the gay couples celebrate their togetherness in Springfield is a parody of several Harry Belafonte songs, particularly his signature "Banana Boat Song". Although Belafonte is straight, his name is dropped in the line "I'm gonna marry my Harry in Springfield town."
Patty calls Selma a "Twisted Sister". Twisted Sister is the name of a heavy metal band.
Marriage laws in the U.S. are chosen by states, not cities.
Although Homer stopped being homophobic in Homer's Phobia, and even lived together with two openly homosexual men in Three Gays of the Condo, he still can be seen holding a sign "Death before gay marriage".
Reverend Lovejoy is unable to cite the book in the Bible condemning homosexuality (allegedly Genesis, Leviticus and others), yet in Homer the Heretic he is able to cite a completely random Bible verse of Homer's choosing from memory (Matthew 21:17).