Trivia: When Castle asks Ryan to say "boyo", it was written that Ryan only said it once. The back and forth volley of "boyos" was ad-libbed by Nathan Fillion and Seamus Dever.
Trivia: Kristin Bauer van Stratten (from True Blood) makes a cameo early in the episode as one of the operators at the phone sex business.
Trivia: Just before Beckett shows up at the loft to admit her feelings for Castle, he ignores an incoming phone call from her. The picture of her on his phone screen is the same picture of her on his digital murder board about her shooting. Not necessarily a goof, since he could simply like that picture of her, but interesting to notice.
Answer: The networks are now having winter breaks. A mid season end of new episodes, when they come back after the new year, it picks up as if several months have gone by. Beckett suggested Valentine's Day as a "chick flick" to watch as she is moved in. Also some episodes are not scheduled to air in order.