Xoxo whoa!

The biggest shocker on Monday's 100th episode of Gossip Girl wasn't Blair Waldorf's (Leighton Meester) royal wedding dress, Serena Van der Woodsen's (Blake Lively) renewed love for Dan Humphrey (Penn Badgley) or Blair's totally mortifying moment at the altar with Prince Louis.

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To longtime fans of the CW show, it was the completely unexpected revelation of Gossip Girl herself: Georgina Sparks, played by Michelle Trachtenberg!

Since the show debuted five years ago, the show's narrator and vicious Upper East Side gossip blogger's identity had never been revealed -- but as the landmark episode wrapped up, the camera finally panned to Georgina, typing away her latest missive and mouthing the blogger's trademark signoff "Xoxo, Gossip Girl."

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Indeed, self-destructive, vindictive, witty loner Sparks -- who executed one vendetta after another against the show's principle cast -- seemed a logical choice as Gossip Girl, who's ruined countless weddings, birthdays, romances and more on the show. (On Monday's episode, Georgina helped undo Blair's perfect royal wedding by secretly taping her pre-wedding confession of unwavering affection for Chuck Bass; the confession was then blasted out to wedding guests and Gossip Girl readers. Blair's wedding resumed, but a vengeful Prince Louis privately vows to Blair that their marriage will be a loveless, obligatory one. Blair escapes the party with her pal Dan who, for his part, has fallen for her himself.)

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Tell Us: What'd you think of last night's episode?

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