* ActorAllusion: Blair referring to Georgina, played by [[Series/BuffyTheVampireSlayer Michelle Trachtenberg]], as a vampire.
** Chuck, played by Londoner Ed Westwick, gets his haircuts at Piccadilly.
** Blair compares Chuck to House. Leighton Meester guest-starred on ''Series/{{House}}'', playing a teenager with a huge crush on the title character. Coincidentally, Chuck and House are both dark, twisted JerkWithAHeartOfGold type characters, and Ed Westwick and Hugh Laurie are both Englishmen while their characters are American.
*** What makes it funnier is the scene where Chuck is talking to Blair about her British boyfriend and says: "''You can't tell me Bertie Wooster is satisfying your needs''."
** Blair mentions herself and Chuck role-playing "''Literature/WutheringHeights''". Ed Westwick had been cast to play Heathcliff in a new remake but was dropped not long before the episode where Blair makes the mentioning aired.
** As a side effect of the show's IdiosyncraticEpisodeNaming, season four's "The Townie" references ''TheTown'' in which Blake Lively has a role. The same season also saw "Panic Roommate" mash up ''PanicRoom'' and ''TheRoommate'' (Leighton Meester plays the title role in the latter), and "Easy J" riff on ''Film/EasyA'' (in which Penn Badgley appears). The first season also has an episode called "Blair Waldorf Must Pie!" (from ''JohnTuckerMustDie'', which also has Penn Badgley) and the SeriesFinale is called "New York, I Love You XOXO" (after ''New York, I Love You'', with Blake Lively[[note]] and Rachel Bilson, who has an uncredited cameo in the episode[[/note]]).
** In Season 1 when Jenny is trying on dresses at Blair's house, Blair tells her a dress is too HannahMontana. TaylorMomsen was one of many actresses considered for the role.
** During the build up to and actual [[spoiler: Blair's wedding]], Wallace Shawn makes at least two ''PrincessBride'' references by name.
** In Season 6, Chuck tells Nate that maybe he needs to find himself a HotTubTimeMachine. Former guest star Sebastian Stan (Carter Baizen) starred in this movie.
** In the final season's "It's Really Complicated," when Serena tells Blair that her ex Steven (played by Barry Watson) tried to get back with her, Blair (who'd rather it was him than Dan again) replies "Ooh, you must be in [[SeventhHeaven seventh heaven]]!"
** Blair has spent time in [[MonteCarlo Monaco]] before.
* DawsonCasting: All the main "teen" cast, with the exception of Jenny (TaylorMomsen was an actual teenager when cast) apply into this trope. Particularly notorious is Nicole Fiscella (Isabel Coates, one of the mean girls), who was born in ''1979''.
** A new example for season 6 is Sage who is 17 played by [[{{Skins}} Sofia Black D'elia]] who was born in 1991, two calendar years older than Momsen.
* DyeingForYourArt: Leighton Meester dyed her blond hair brown before her audition, and kept it brown whenever the show was filming.
** The awful dreads they put on Jessica Szohr have to count.
* EnforcedMethodActing: Billy Baldwin refused to meet Blake Lively before their first scene together because he wanted the experience of seeing your father/daughter again after 14 years to be as real for both of them as possible. He also stated that he pretended Blake was his real life daughter.
* HeyItsThatGuy: Cyrus Rose is [[Film/ThePrincessBride Vizzini]]. Judging by the way he out-schemed Blair, he's gotten a little better at his planning.
** Inconceivable!
** Before portraying Bree Buckley in Season 3, Joanna Garcia played [[{{Privileged}} Megan Smith]], [[{{Are You Afraid Of The Dark}} Sam]], and [[{{Reba}} Cheyenne]].
** Before playing Rufus, Matthew Settle portrayed one of the most [[{{Memetic Badass}} badass people ever]], [[strike:Lt.]] Captain [[Series/BandOfBrothers Ron Spiers]].
*** His daughter is [[Film/HowTheGrinchStoleChristmas Cindy Lou Who]].
*** His son is [[JohnTuckerMustDie Scott Tucker]]
** Lily Humphrey used to be FemmeFatale [[Series/TheAdventuresOfBriscoCountyJr Dixie Cousins]] and IntrepidReporter [[Series/KindredTheEmbraced Caitlin Byrne]].
** One for the UK fans: Mr Smith, the guy Agnes and Jenny visit in "Bonfire of the Vanity" and who Jenny later returns to for help in launching her fashion line, is the guy from the Orange adverts.
** Georgina is [[Series/BuffyTheVampireSlayer Dawn Summers]], who, for Buffy fans at least, will look 15 for all eternity.
** In her blond days, Blair stalked Series/{{House}}.
*** Even better (and brunetter), she "had a long and storied reign as the gossip queen of [[Series/VeronicaMars Neptune High]]."
** Chuck's life was saved in Prague by [[Film/HarryPotter Fleur Delacour]]!
*** And [[Film/HarryPotter Tom Riddle]] is Chuck's valet.
** Juliet was the little devil on [[Series/{{Supernatural}} Sam Winchester's]] shoulder.
** Russell Thorpe was anal-retentive CFO Stanley Babson on [[{{HBO}} [=HBO=]]]'s ''Arli$$'', and Doctor Cox's best friend from college on ''Series/{{Scrubs}}''.
** Serena was conned by one of [[TheSocialNetwork the Winklevii]].
** What about LizzieMcGuire as Vanessa's roommate?
** The "Valley Girls" BackDoorPilot features [[Series/AmericanDreams Meg Pryor]], [[Series/VeronicaMars Dick Casablanca and Gia Goodman]], with [[{{Hellcats}} Dan Patch]] as the antagonist.
** Jenny's model friend and later enemy is [[Series/TheOC Kaitlin Cooper]].
** [[Series/{{Alias}} Anna Espinosa]] is Gabriela Abrams.
** Why is Nate dating a [[{{Skins}} lesbian?]]
** Serena used to [[TheSisterhoodOfTheTravelingPants wear the exact same jeans]] as Series/UglyBetty, Series/JoanOfArcadia and [[Series/GilmoreGirls Rory Gilmore]].
** [[SeventhHeaven Matt Camden]] has a teenage daughter already.
* HeyItsThatVoice: [[Series/VeronicaMars Kristen Bell]] is Gossip Girl, though she's uncredited.
** Also the Japanese version has [[Creator/DaisukeNamikawa Ulquiorra]] with [[Creator/RomiPark Hitsugaya]] as siblings, [[YukoKaida Marida]] as Serena and Starkiller as Chuck Bass, and [[Creator/ChiakiTakahashi Litchi]] spilling the gossip.
** In Hungary and Brazil, Blair and the Gossip Girl are both [[WesternAnimation/TotalDrama Katie and Zoey]].
* MeanCharacterNiceActor: Leighton Meester is by all accounts a lot easier to take than Blair Waldorf (which admittedly wouldn't be hard).
* ScrewedByTheNetwork: The ''Valley Girls'' spinoff was picked up, but then cancelled before it could even air.
* StillbornFranchise: 2008 saw the release of ''OMFGG Original Music Featured on Gossip Girl No. 1.'' There would not be a No. 2 (the CD didn't even include the show's opening/closing music for some reason).
* ThrowItIn: This ad-libbed dialogue in the last scene from season two:
-->'''Blair''': (''after Chuck told her he loves her'') But, can you say it twice? No I'm serious, say it twice.
-->'''Chuck''': I love you. I love you. That's three. Here's four - I love you.
* WhatCouldHaveBeen: Mischa Barton was approached to play Georgina Sparks even after [[TheOC the last time she worked with Josh Schwartz]], but she turned them down. Enter Michelle Trachtenberg.
* WordOfGod: Josh Schwartz and Stephanie Savage have cruelly crushed hopes for [[FanPreferredCouple Vanessa/Rufus]], saying that fans who want them are barking up the wrong tree.
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