The Untitled Robot Parody is a parody of the Transformers franchise from Hasbro.
The toy that blinks its lights at Bart in the 99-cent Store resembles the original Optimus Prime cab-over Semi of the Transformers cartoon from 1984.
Homer and Ned's cars transform into robots resembling Optimus Prime and Megatron.
The beginning of "How to Get Ahead in Dead-Vertising" is a parody of Mad Men.
Milhouse's prayer to the Grand Pumpkin is similar to the Nicene Creed.
The dance scene in "It's the Grand Pumpkin, Milhouse" is a parody of the dance scene in A Charlie Brown Christmas.
Trivia
All the characters shown in the title sequence of "How to Get Ahead in Dead-Vertising" are: Marge, Patty, Selma, Edna, Grampa, Mona, Homer, Lurleen Lumpkin, Ruth Powers, Maggie, Rod, Ned, Maude, Todd, Medicine Woman (from The Simpsons Movie), Spiderpig, Lisa, Agnes Skinner, and Amber (from "Viva Ned Flanders") and Lindsay Neagle.
Bart's gift list from "Untitled Robot Parody" includes mom (Marge), Homer, Maggie, Grandpa, Grandma Bouvier, Santa's Little Helper, Aunt Patty, Aunt Selma, Ling, Milhouse, and Lisa.
Nelson's line in his Halloween carol, "The Grand Pumpkin is super gay" caught the ire of anti-gay defamation groups who were protesting against people using the word "gay" to mean something inferior or bad.
Censorship
In the UK, the following scenes are cut from all three sections:
"Untitled Robot Parody": The appearance of the Sex Toy Robot.
"How to Get Ahead in Dead-Vertisting": Krusty getting shredded in the woodchipper, Homer strangling, stabbing, and beating Prince with his own guitar, and Krusty shooting Homer in the head.
"It's The Grand Pumpkin, Milhouse": The Grand Pumpkin puking after learning that pumpkin bread is made of pumpkins (and not bread for pumpkins), Nelson calling the Grand Pumpkin a racist because he doesn't care that Nelson is going to carve a yellow pumpkin, and Tom Turkey blowing the Grand Pumpkin's brains out by blowing through a cornucopia (along with the Grand Pumpkin's dying words).
Previous Episode References
The Sex Toy Robot sounds like Andre (the sleazy guy Patty and Selma wanted Marge to date while Homer is in the hospital) from "Homer's Triple Bypass."
"Hungry, Hungry Homer": Homer sleeps on the roof of the house a la Snoopy from the Peanuts cartoons and Bart says, "Good grief."
"Treehouse of Horror XI": A "Treehouse of Horror" story where Homer dies and John Wayne is shown in the afterlife (only in Treehouse of Horror XI, he's in Hell)
"Saddlesore Galactica": Homer is chased by a group of angry people riding on horses (the jockey elves/the dead celebrities). Also, John Lennon's line about eating brains is similar to one of the jockey elves' threats to eat Homer's brain.
"Treehouse of Horror III": A "Treehouse of Horror" story featuring malevolent toys come to life ("Clown Without Pity"/"Untitled Robot Parody")
"Last Temptation of Krust" and "When You Dish Upon a Star": Reference to dead celebrities being used for advertisements.
"Treehouse of Horror II": Both episodes have homages to It's The Great Pumpkin, Charlie Brown
"Lisa vs. Malibu Stacy": Lisa has a talking Stacy doll that's activated by a pull-string (even though pull-string toys are very outdated).
"Sideshow Bob Roberts": Homer votes during an election and a voting fraud scandal is revealed.
