PIC: Penn Badgley, Zoe Kravitz Hold Hands

Sunrise, sunset. Just as Blake Lively has ended her five-month romance, her ex Penn Badgley is going public with a new woman: Zoe Kravitz!

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On Tuesday, the Gossip Girl actor, 24, held hands with the X-Men: First Class star, 22, during an affectionate stroll in NYC's Soho neighborhood. Before going their separate ways, the hot new couple shared a kiss. See more pics of Penn and Zoe from PopSugar!

"They're doing great," a source close to the pair tells Us Weekly. "So happy!"

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The sexy twosome first started palling around in NYC over the summer -- supping at Brooklyn's Five Leaves restaurant July 16, sharing a 1:45 a.m. cab together following a July 18 Friends with Benefits premiere bash, and catching a Horrible Bosses showing the following day.

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Badgley and Gossip Girl costar Lively, 24, called it quits after three years together in October 2010. (On Tuesday, reps for Lively and DiCaprio, 36, confirmed exclusively to Us that they've split and "remain friends.") Kravitz (the stunning daughter of rocker Lenny Kravitz and Cosby Show's Lisa Bonet) most recently dated her hot X Men costar Michael Fassbender.

Tell Us: Do Badgley and Kravitz make a cute couple?