Continuity mistake: In the scene where Shawn is brought into his childhood bedroom to investigate Allison's abduction, there is a "Peeping Tom" band poster visible behind him for a few seconds. This was Shawn's bedroom in the 90's, and "Peeping Tom" didn't exist until 2006.
Ferry Tale - S5-E7
Continuity mistake: When Young Shawn tapes his and Gus' legs together he puts the tape on the ground. When they start to run it has disappeared.
Chosen answer: "Psych: The Musical" was supposed to air during the regular season 7 schedule, before Chief Vick is suspended and Jules discovers Shawn's lie, but the network decided to push it back to air as a special episode, sort of as a tie in with the holiday season and a lead in to season 8, which was to begin only a couple of months later.