This is the first time that Blair has a dream in which she is a character that was played by Audrey Hepburn in a movie. The second time was in The Blair Bitch Project (2008). The third time was in New Haven Can Wait (2008). The fourth time was in Seder Anything (2009).
The dress Serena wears in Blair's dream is the same dress Blair wore in the first episode.
The only time during the series actor Ed Westwick speaks close to his native accent is in this episode during The Lost Weekend pub crawl. When Chuck tells the guys "Remember, don't stick your shillelagh in the wrong pot o' gold".
Josh Safran stated that, in his opinion, Chuck's basketball outfit from this episode was the worst outfit in the entire series (but that he loves it for that exact reason.)