อ้างอิงจาก:

Spotted: Two fewer troublemakers on the Upper East Side.
TVLine has learned exclusively that Gossip Girl is parting ways with Taylor Momsen (Jenny) and Jessica Szohr (Vanessa).
A source close to the show confirms that the two actresses will not be returning as series regulars for the CW soap’s upcoming fifth season, but added that both have been invited back on a guest star basis.
Ask Ausiello: Spoilers on Grey’s Anatomy, Chuck, Community, Parks and Recreation and More!
The insider also confirms that GG‘s core five — Blake Lively (Serena), Leighton Meester (Blair) Penn Badgley (Dan), Ed Westwick (Chuck) and Chace Crawford (Nate) — will all be back in the fall. Additionally, Kaylee DeFer — who joined the cast this spring as Serena’s rabble-rousing cousin Charlie — has been promoted to series regular status.
Glee Exclusive: Look Who’s Returning!
The departures of Momsen and Szohr hardly come as a complete surprise. Momsen — who has made no secret of her desire to make music her primary focus — has appeared in only a handful of episodes this season. Similarly, Szohr’s alter ego has been given little to do save for a little eavesdropping and meddling here and there. What’s more, Vanessa recently revealed that she was leaving town to study abroad.