Leighton Meester in black leather. Photo: Axelle Woussen, Bauer-Griffin

American Eagle Outfitters may not seem like the typical brand to draw a solid celebrity crowd, but tonight's store opening in NYC's Times Square proved just the opposite.

With Pete Wentz in the DJ booth, and "Gossip Girl" Leighton Meester slated to perform her new single, the 3-story shop was wall to wall with fashion VIPs and famous faces.

Many Gossip cast mates were in attendance, from Blair's steamy ex-fling Lord Marcus Beaton (AKA actor Patrick Heusinger), to current rivals Georgina (Michelle Trachtenberg) and Vanessa (Jessica Szhor). The supportive stars even fought their way to the front of the (sweaty, packed, semi-violent) crowd to get to a front-row view when buddy Meester took the stage.

The outfit the actress-turned-singer chose was a black leather low-cut mini, with a leather peek-a-boo bandeau underneath. Looks like Meester and co-star Blake Lively have one thing in common: They're not afraid to under-dress.

While we didn't catch the big performance, a pal in attendance told us "she was good!" and "Project Runway" alum Christian Siriano said of the star's music, "I actually love it! Don't judge me."

On our way out, we caught up with co-star Jessica Szhor, who looked drop-dead gorgeous in person. We asked about her hair, which was thick, full, and perfectly "undone." Her secret? Good genes.

It turns out that straight-but-slightly-wavy texture is natural. And all the star has to do is skip a shampoo to get it just right:

"My hair works better when it's dirty, so if I don't wash it for a couple days, it could take me like two minutes," she told us.

We'll try not to be too jealous.