(From Wikipedia, not in order.)
IJLSA: "The International Justice League of Super-Acquaintances" is a parody of the Justice League. However, the Elastic Waistband is a parody of Mr. Fantastic and Plastic Man and Captain Magma is a parody of the Human Torch from the Fantastic 4. Miss Appear was also a parody of the Invisible Woman. Also, The Quickster is a parody of The Flash, an actual member of the Justice League.
This episode made its first DVD debut on the DVD disc for another episode, "Fear of a Krabby Patty". There were also storybords for these episodes, including this episode. The storyboard version of this episode was called "Super Friends", was 19 minutes long, including the opening theme song for the series and the end credits, contained a few deleted scenes, two deleted characters, and one added character with a different name. Then, the episode debut again in the DVD release of the third season.
Tom Kenny voices the Dirty Bubble in this episode instead of Charles Nelson Reilly.
E.V.I.L. stands for "Every Villain Is Lemons." Note that villain is misspelt as "Villian" in the episode.