An item named "Skittlebrau" can been seen in the 33¢ store. The item was made up by Homer in the episode "Bart Star"; however, Apu claimed there was no such thing (unless the product came out months after the events of "Bart Star," or Apu could not have heard of the product, despite it being on the market, or the product is only known in discount stores).
Numerous "That 70's Show" mugs can also be seen inside the 33¢ store.
This episode was banned in Japan due to scenes that are considered offensive to Japanese culture (the scene regarding the Hello Kitty factory (due to the implication that the various Hello Kitty products were created by burning various cats alive) the "Battling Seizure Robots" parody (kind of based on the Pokemon episode "Dennō Senshi Porigon" that caused about 700 people to go to hospital in Japan, which is why the Japanese people wouldn't want a reference to it, see this ) Homer tossing the Emperor of Japan into a sumo thong Dumpster and declaring himself "Emperor Clobbersaurus" before getting arrested, and the Japanese game show sequence). The episode is also not included in the Japanese version of the season 10 DVD. It may also have been banned in South Korea due to its rocky history with Japan in the first half of the 20th century.
Homer is clearly not impacted during the first "seizure" scene, and just "goes along" with the family, rolling around on the ground. When the show returns he seems to be impacted by it just like everyone else, as his eyes enlarge. Although it is possible that during the first set of seizures he was not actually looking at the TV. (He was just trying to fit in the first time).
The Boeing 707-320 was produced from 1959-1970, so by this point the plane would be 20-30 years old.
At the Americatown Restaurant in the overhead shot Connecticut, Delaware, Hawaii, and Alaska are missing.
Marge says to Homer on the plane that he liked the film Rashomon. Homer's line, "That's not how I remembered it," is a reference to the famous Rashomon-style storytelling, in which three (or four) people tell the same story, and often exaggerate or omit details.
Whilst in the hotel, Bart watches an anime cartoon called "Battling Seizure Robots", which features a robot with its eyes flashing so quickly that it triggers seizures. This is based on the banned Pokémon episode, "Electric Soldier Porygon", in which a scene with rapid lighting flashes sent 685 (310 boys, 375 girls) children into seizures.
While at America Town Homer tells Bart that he once understood a man from Nantucket, a reference to the many limericks, in which the name of the island of Nantucket creates obscene rhymes and puns and the protagonist is typically portrayed as a well-endowed, hypersexualized persona. He then tells Bart "Let's just say the stories about him are greatly exaggerated."
While walking the streets Homer and Bart see Woody Allen filming a commercial for crackers. Woody asks himself how did he get to this low point in his career and then remembers and says "OH ya" in reference to his child abuse allegations.
When Barney is trying to imitate Homer, he says "That boy ain't right" referencing Hank Hill's catchphrase in "King of the Hill."
When Godzilla peers in through the plane window at Lisa, it is a reference to Jurassic Park when the T-Rex peers in through the Jeep window.
When Database is at The Java Server, he is using a gray computer but in the next scene he is using an orange computer, then he is using a gray computer again.
During the Mega-Savings Seminar show, Mr. Burns was seated two chairs away from the end and Mr. Monopoly was one chair away, but when Mr. Monopoly enters the car, Mr. Burns is now one chair away to the end.
Marge drops one of her shoes into the 'volcano' but in the next scene when the entire family plummets down, her shoe is back on.
Marge doesn't appear to be wearing her green dress underneath her work clothes at the fish gutting factory, but she is wearing it right before the game show ad goes on.
During the airplane trip back to Springfield, the flight attendant refers to Mothra as a 'he,' even though she is female in the Godzilla franchise. There are multiple Mothras in the movies, so some of them are presumably male.
Chuck Garabedian said that with a mega savers vacation you go to the airport, wait for some no shows and buy their tickets for a fraction of the price, however on the day of the flight, tickets are much more expensive, and also you can't buy the tickets of no shows.
The Simpsons are shown to be in departures (airside) before getting their tickets and boarding passes, however before security makes inspections all passengers must show their boarding pass in order to proceed. Of course such practices mainly rose out of response to 9/11, which this episode predates.
When the subjects for the gameshow are presented, the host gives a brief translation. Properly translated, they are "Painful!" "Why do you do that!?" and "Let me die!"