Actor Allusion: Matheson is gleeful at the beginning over someone named "Reynolds" retiring due to his wife's sickness. Mekhi Phifer played Ben Reynolds in Lie to Me.
Executive Meddling: Bill Pullman mentioned in an interview that Oswald Danes ended up dying because the lawyers said so. Not that we can blame them, but still.
Fan Nickname: "The Triangle", because of the revolving triangle that appears on the cellphones of their lackeys. Those who have read the brief Starz synopses for later episodes knew they were called the Three Families, however.
Recycled Set: Scenes filmed at Ontario International Airport are set in airports in Los Angeles, Shanghai and Buenos Aires.
What Could Have Been: Miracle Day was come upon after the series creator Russell T. Davies found his efforts to sell the format rights to the major American networks were hitting a brick wall. Davies wanted to retain continuity ties to the British series, including John Barrowman in the lead role, whereas most of the people he was in talks with at the networks suggested remaking the show wholesale for American audiences, including recasting all of the lead roles, as well as downplaying/dropping Jack's omnisexuality (details vary on the full extent of this). Davies eventually found Starz Entertainment, who were the only guys that were happy to make a true co-production to Davies' specifications.