PHOTOS: Anna Wintour & Renée Zellweger Have an 'Issue'

You wouldn't guess by looking at her, but Renée Zellweger actually enjoyed herself at last night's premiere of The September Issue, a new documentary that follows Vogue editor Anna Wintour as she strives to put together the mag's huge fall fashion issue. A horde of fashion-friendly celebs, including Sienna Miller and Diddy came out for the event.

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