Fashion Week's first confirmed celebrity has arrived, and she's major: as part of her Factory Girl promotional duties, Sienna Miller hits New York soil next week for a five-day stint including her movie premiere, press interviews, and a few front-row appearances to help with the hype. We expect to spot Ms. Miller with her pals The MisShapes, and to steal the light from other starlets at Marc Jacobs, Zac, and maybe Matthew Williamson. We also hope Sienna supports some new designers with her boldface presence - she'd look hot in Ruffian, Sari Gueron, Chris Benz, and Vena Cava, too. Also on hand for the runways: Well, Charlize Theron's in town promoting not one but two movies; expect to see her at the Designers for Darfur show hosted by Lydia Hearst. Then there's Sienna's Factory Girl co-star, Mena Suvari. Is she about to experience a major resurrection, American Beauty style? And who else is coming out for the catwalks? Email us - email@example.com - if you've got any ideas. Meanwhile, we're definitely sitting on more gossip of our own, and we'll bring you more news when the time is right.