Gossip Girl – Katie Cassidy joins Cast

Look out, Blair: Ex-Melrose Place vamp Katie Cassidy is relocating to Manhattan.

Sources confirm to me exclusively that Cassidy — who was arguably the best thing about last season’s ill-fated Melrose reboot — is staying in the CW fold with a multi-episode arc on Gossip Girl.

She’ll play a student at Columbia and a love interest for fellow undergrad Nate (Chace Crawford).

This next bit probably goes without saying, but a Gossip source tells me that Cassidy’s character “will make trouble” for several Upper East Siders, adding, “She is not what she appears.”

Cassidy will first air in the season 4 premiere.

Coincidentally, Cassidy is currently in Paris shooting the teen adventure comedy Monte Carlo alongside fellow Gossip girl Leighton Meester (Blair). Thoughts? Does Cassidy’s casting warrant an enthusiastic “Yes!” or an apathetic “Meh?” (Hint: The correct answer is “Yes!”)