We've been to many concerts where the headliner had to scream at the lazy audience to get up and dance. Heck, even Madonna had to do it a few times. But when Gossip Girl's Leighton Meester took to the mic at last night's grand opening party for Klutch in the old Opium space, you'd have thought she was Lady Gaga. Either that, or the celeb-spotted audience was just hopped up on Red Bull or something. Take Twilight's Kellan Lutz, for instance, sporting a dandy look of all black with a newsboy cap and scarf. Although Lutz was seemingly distracted by the attention of an unidentified woman, as soon as Meester took to the stage, he went from suave teen heartthrob to an over excited guest star on Barney, cheering, jumping and dancing during her performance. Lutz was very pleased with his pal's performance, hopping over to the DJ booth to congratulate her. Gossip Girl and Twilight guy danced a little, hung out with the band and then parted ways as Twilight guy went to hang out with the guys from the band called Boys Like Girls. Meester, incidentally, sporting a short black dress with cutouts, worked the crowd like a pro, standing atop the bar singing in between grabbing fans and famous friends including Lutz, Project Runway's Christian Siriano and his boyfriend, and Melrose Place revisited star Colin Egglesfield. After Meester gave a big hug to Lutz, she danced away with her bandmates and backup dancers as Boys Like Girls took over the stage during which time Egglesfield and Lutz made like bff's in between sips of Ketel One and cranberry. Seasoned club types, ahem, said it was refreshing to see such a young crowd getting their grooves on, but couldn't help reminiscing about the nights when that club was in the clutch of a much different caliber of celebrities, the kind of which the only club they're belonging to these days is AARP.