Revealing mistake: When the couple is breakfasting in Brooklyn their mugs are empty.
Continuity mistake: When Serena is saying goodbye to Dan, rain is pouring on the angle focusing him, but not on the angle focusing her. This changes back and forth.
Trivia: Leighton Meester is a natural blonde, and dyes her hair for her role.
Question: Who was Georgina Sparks talking to in Russian, and why did she only have "one day"?