Whereas Anthony Head does not actually play guitar for Behind Blue Eyes in Where the Wild Things Are (2000) (music supervisor John King did), this time he both sings and plays Free Bird (1973), by American rock band Lynyrd Skynyrd.
During the scene where Anya and Tara are hiding in the bathroom, the voices arguing in the background is actually the argument in Pangs (1999), where Willow and Giles are arguing about what to do regarding the indigenous vengeance spirit.
When Spike tells Willow that the rest of the Scoobies don't think she's much of a "wiz" anymore, she responds by saying that she is a wiz, "if ever a wiz there was". This is a paraphrase from the song "We're off to See the Wizard" from The Wizard of Oz (1939).
This line from Spike was cut for length: "Now that you've turned Super Wicca and you're damn near Amish. All candles and hand-ground herbs..."
The title refers to Yoko Ono. Yoko Ono and John Lennon's son, Sean Lennon, previously appeared in the premiere of Season 2, "When She Was Bad", performing in his band Cibo Matto at the Bronze.