Or she's just grinning because she gets to wear that fab outfit on the Gossip Girl set!

Blake Lively, who's currently starring in the Ben Affleck flick The Town in theaters, appeared absolutely ecstatic yesterday in New York while filming her hit TV show. You know Leighton is all annoyed that Blake is a movie star for a week - you know it!

Poor Leighton! She's been shooting Monte Carlo and Gossip Girl all summer with no break. All those fabulous outfits (well, sorta) and running around Paris and NYC... it's a rough life, people!

But we love Little Miss Leighton and don't want to see her all grumpy on set. Plus we're super excited to see her in the new Gwyneth Paltrow movie Country Strong!

Minus the crazy! Not to mention the fact that we adore her chill yet sexy outfit. I imagine it's actually Leighton's and not Blair's! Check out more of the Gossip Girl cast in our gallery below...

Blake Lively also made sure to show off her bra in a see-through top. If you've got it, flaunt it!

Katie Cassidy has begun filming her stint on Gossip Girl! Loves it.

Leighton Meester shot scenes in New York with her Monte Carlo co-star - how random, right? - for GG on Wednesday... and she doesn't look happy about it! Of course, that's probably just the Blair in her.

Meanwhile, check out pretty boy Chace Crawford and Blake on set together. Two cute!

The shoot must go on! Gossip Girl starlets Blake Lively and Leighton Meester stand under their umbrella-ellas while shooting a scene in the Big Apple for their much talked about show. Loves their outfits equally this time around! How rare.

Talk about a fug dress! Poor Leighton Meester - she's the best thing about Gossip Girl (which has resumed filming in NYC) but always gets stuck with the worst costumes. It's a curse!

Sidebar, does anyone still watch this show after three long seasons? Not as intriguing as it used to be!

XOXO.

Blake Lively and Leighton Meester continued their womance (or is it a sistemance?) in France, where they're currently shooting the upcoming season of Gossip Girl.

We're not entirely sure where this storyline is going, but the girls have been photographed feeding each other French macarons, going in for a kiss, and now holding hands in Paris!

But it wasn't ALL just wine and roses for the pair.

Click through if you want a little spoiler alert for the new season:

And then Leighton (slash Blair) went on a shopping spree! Check out more of the Gossip Girl girls shopping and smooching on set in Paris.

Dressing in all these sexy outfits and shopping? Such a hard life they live!