After Jor-El saves Chloe, Clark calls him directly "Father" for the first and so far only time. He has actually referred to Jor-El as his father on numerous occasions but this is the only instance where he addresses him as Father during one of their conversations.
The name Doomsday is used for the first time.
The name of the author of Tales of the Weird & Unexplained, Aleya Naiman, is a nod to the show's prop master.
Jimmy is quoting the lyrics to the 1954 song "Fly Me to the Moon", by songwriter Bart Howard, when he tells Davis that Chloe is "All I long for, all I worship and adore". The song has been recorded by several singers, including Frank Sinatra, who recorded it in 1964.
Chloe says to Clark that Metropolis is something like a two hour commute from Smallville. The distance between Smallville and Metropolis has been an inconsistency in the show since Season One's "Nicodemus".