Is 40 the new 30 in Hollywood?

A-lister Ben Affleck joins the 40 club this week and he's not the only youthful looking star to hit this major milestone in the month of August. You might be surprised to find out which other stars turn the big 4-0 this year! Plus, Naomi Watt's was spotted as a brunette on the set of the biopic Diana on Tuesday, and Ellen DeGeneres loves Miley Cyrus' new 'do so much that she copied the former Disney star's look. Who do you think looks best, Miley or Ellen?

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