Just saw American Sniper, and I'm calling it:

Sienna Miller is the most beautiful woman I've ever seen. She really should ditch the peroxide and stick with dark hair. There's something about it that brings out her gorgeous facial features. I couldn't take my eyes off her every single second she was on screen. As a blonde, she's pretty, but just another blonde. As a brunette, she is out-of-this-world, unbelievably smoking hot.

I even endured the horrible GI Joe movie because I saw her in previews with black hair and was just floored by her beauty.