This episode does not have anything to do with film critic Roger Ebert, aside from the constellation of him, shown for a couple of seconds in the planetarium. The title is actually a reaction from Trey Parker and Matt Stone after Ebert gave their films Orgazmo (1997) and BASEketball (1998) poor ratings as well as negative reviews. Ebert was a fan of the series, however, and gave a rave review to South Park: Bigger, Longer & Uncut (1999).
Cartman's middle name is revealed as the Cheesy Poofs casting director calls him Eric Theodore Cartman.
The poor little girl with the windswept hair who is in the call back with Cartman and the others is none other than Cosette, the girl from Les Miserables. In the novel, her guardian, Jean Valjean, long before he met her, was thrown in prison for stealing bread. Cartman eliminates the girl from the competition by saying bread is being given away outside. Behind her is a poster for the Les Miserable musical which bears the question, "Who will be the next Cosette?".
The Latin inscription, "Me transmitte sursum, Caledoni!" seen above the entrance to the Planetarium [loosely] translates as, "Beam me up, Scotty!"
The character of Dr. Adams is based on the character Dr. Tristan Adams from Dagger of the Mind (1966). Both characters are dressed in black turtle neck sweaters with an ocean green short sleeve robe.