This is the first episode where Mila Kunis sings for Meg perfectly instead of being dubbed and instead of speak-singing like in the original version of "All I Really Want for Christmas" and singing off-key like on the Family Guy: Live in Vegas album.
In the northern hemisphere, birds fly south for the winter. Therefore, the truckload of birds should have been leaving Canada, not entering.
When Brian tries to start his car after the accident, you hear the engine try to turn over. Being a 2004 Toyota Prius, it should have tried to start in electric mode.
Brian and Stewie begin delivering presents in the North-Eastern United States. Santa would actually need to begin his delivery of presents in the country of Kiribati. It is the first country west of the International Date Line, therefore it starts December 25 before all other countries.
The DVD commentary reports that the live-action sequences were shot on the set of Bones.
The commentary also noted that Dan was not killed after being beaten with a baseball bat. This is why he was tied up along with his wife.
This episode won a 2011 Emmy for Outstanding Sound Mixing for Production Sound Mixer Patrick Clark and Sound Re-Recording Mixer James F. Fitzpatrick.