Some of the restaurants the Simpsons pass after leaving church: Griddler on the Roof, TGI Fried Eggs, Luftwaffles, Bodacious Frittatas, and Buffet the Hunger Slayer.
The Springfield Opera House looks like the Sydney Opera House.
The title is based on the opera "The Barber of Seville, or The Useless Precaution" and contains two acts by Gioachino Rossini with a libretto by Cesare Sterbini. The unique thing is that this Italian Opera premiered in New York City.
Homer paints a portrait on the ceiling that's a parody of Michelangelo's The Creation of Adam on the ceiling of the Sistine Chapel.
Bart's chalkboard gag is "The Wall Street Journal is better than ever." This is a reference to the recent takeover of the Wall Street Journal by News Corporation, the mass media corporation of Fox owner Rupert Murdoch.