When Dean says "Welcome to the party, pal" this references the same quote that John McClain says in Die Hard (1988).
First time Crowley calls Sam "Bullwinkle" instead of just "Moose".
Mark Sheppard and Tahmoh Penikett have starred together in the TV Shows Dollhouse (2009) and Battlestar Galactica (2004).
Crowley says, "The three amigos ride again!" Three Amigos! (1986) is a comedy film starring Steve Martin, Chevy Chase, and Martin Short.
Sarah Deakins (Margey) appeared in an episode of Battlestar Galactica (2004) which starred Tahmoh Penikett (Gadreel).