Peter makes a reference to the Alien movies when he says "Because in space no one can hear you scream"
This Is The First Family Guy (1999) Episode To Have Cleveland In The Intro After He Returned From Being On The Cleveland Show (2009)
During the theme song (not the intro to the episode) when Stewie is watching everyone else singing, if you listen carefully, the theme song does have Stewie's vocal tracks muted while singing.