Combat Hoots: Sienna Miller has a lot riding on "G.I. Joe: The Rise of Cobra." This is her first big-budget action flick, and its performance could mean the difference between being a bankable Hollywood leading lady or a B-list tabloid target best known as "that starlet Jude Law cheated on with the nanny" and "that starlet who cavorted topless with a still-married Balthazar Getty." Sienna seems to be taking her promotional duties seriously by suiting up for box office battle, even clomping around in combat boots, albeit peep-toed, ridiculously expensive designer combat boots. For the action flick's Tokyo premiere, the actress drops a glitter bomb on the red carpet in a "Dynasty"-shouldered sparkly jacket, matching splotchy pants, and a twinkling blue shirt that looks forlorn without its usual accessories: a dozen gold chains, fluffy tufts of chest hair, and the thumping strains of "Disco Inferno." In an haute couture instant, Miller lays waste to unprotected corneas with a blinding flash of gaudiness that's designed to get people talking, although it remains to be seen whether they'll be saying anything more than, "My eyes! My eyes!"