Even though he appeared on the promotional poster, Tim does not appear in this episode. Neither do Lester or Holt.
In the episode, a character is seen with a Herbert mask on for a second.
A Bender costume from Futurama can be seen when Donna and Cleveland chase Robert Rodriguez in the pedicab.
The opera music playing during the fountain scene is soprano Maria Callas, singing the aria "La mamma morta", from Andrea Chénier by Umberto Giordano.
Cleveland Jr. waits in line with other costumed nerds for a live staging of Dr. Horrible's Sing-Along Blog, a viral sensation created by Joss Whedon. While on line, one nerd says that Firefly (another Whedon creation) is overrated, to which Cleveland Jr. agrees.
Cleveland calls Donna "Donna Tubbs" in a flashback as a youth. Despite marrying Robert Tubbs, her mother Dee Dee Tubbs also shares the same surname.