Jerry's cab fare in Tuscany would work out to $63.75 based on the conversion rate established by Mr. Ciccio (Poppie's uncle).
George compares the size of Tuscany, one of the 20 regions of Italy, to that of North Dakota. In reality, at 8,876 square miles, it is only one-eighth the area (although it does have six times the population).
Notice when George is asking the security guard about having a chair. If you look in the background you'll see the same guy walk by twice from the right to the left.
When Jackie Chiles asks Kramer who put the top on he answers "they put the top on". However, in the previous episode "The Postponement" you can actually see Kramer putting the top on himself when he and Jerry are standing in the line outside the movie theater.
Elaine: Did you know that Mozart died while he was writing The Requiem?
Jerry: Yeah, everyone knows that; it was in Amadeus.
Jackie: "I'll take it?" "I'll take it?" Who told you to take it? Did I tell you to take it?
Jackie: I know the Maestro didn't tell you to take it. He wasn't there!
Jackie Chiles: You put the balm on? Who told you to put the balm on? I didn't tell you to put the balm on. Why'd you put the balm on?
Phil Morris makes his debut as recurring character Jackie Chiles. In reality, he had worked with the Seinfeld crew earlier as the spokesman for "Mayor" Dinkins in an alternate version of Season Five's "The Non-Fat Yogurt" episode. Since Giuliani won the election, those scenes never aired. The alternate version is available, however, as an extra on the DVD.