The Christmas fire log channel and Lacey's love for it, as first mentioned in 'Cable Excess' (#5.1), makes an appearance here.
Oscar tells Karen her Christmas gift in exchange for wearing her cop hat. When he puts the hat on he exclaims "Jeez, you got a big head!" This may be a bit of an inside joke, since in the DVD commentary of "Whataphobia" Tara Spencer-Nairn states that she has quite a small head, and they have to "time out" when she can wear the cop hat because it leaves a mark on her forehead.