Bud's line, "My god, it's full of stars," references 2001: A Space Oddysey. Bowman says the same phrase when he disappears into the monolith.
According to the DVD commentary this is the creators least favorite episode of the season.
This episode parodies a 1962 film titled "The Manchurian Candidate," which Abraham Lincoln's ghost mentions. The original film stars Frank Sinatra and Angela Lansbury. The 2004 remake stars Denzel Washington. The plot centers around the brainwashed son of a prominent right-wing political family, who becomes an unwitting assassin in an international conspiracy.
The title is a play on words; the secondary meaning of "coming" references the moment when Bud's says, "My god, it's full of stars."