Continuity mistake: In the scene near the end when Faith is putting Joyce's lipstick on in the mirror and taunting her, it is obvious that the make-up department forgot to put Faith's tattoo on her upper arm. It's obvious if you watch back and forth between the mirror and the shot of Faith standing and turning, there is no evidence of a tattoo that has been established Faith has in the previous season.
Continuity mistake: When Spike finally gets into the area where the gem is and Harmony follows him up there, he puts on that necklace thinking it's the gem. When he realizes Harmony has the gem it shows him taking off the necklace. It cuts to another shot and then shows him again with the necklace, but minus the charm.
Continuity mistake: When Buffy is fighting the vampires at the end of the episode, she grabs a tennis racket and smashes the brunette vampire over the head. She falls over the back of the couch and we hear the thud of her landing, however in the wide shot of the couch the vampire has just started to go over the back.
Continuity mistake: In the scene where Buffy and Kathy are deliberately infuriating each other (tapping pencils and cracking eggs) there are several lights on throughout the room (on Buffy's desk, above Kathy's computer, in the kitchenette) yet when Buffy turns out her bedside lamp, the entire area is thrown into darkness.
Continuity mistake: When Buffy and Willow are talking about the sham of Thanksgiving Day at the groundbreaking ceremony, on one angle (the one where Buffy's face is shown) there is a strong wind blowing, moving their hair about, but in the other (when you can see Willow's face) their hair aren't moving.