4. Rooney Mara

2011 key role: 'The Girl With the Dragon Tattoo'

Previously known for 'The Social Network' -- and for being Kate Mara's little sister -- Rooney Mara earned the coveted role of Lisbeth Salender in David Fincher's highly anticipated adaptation of 'The Girl With the Dragon Tattoo.' Beating out the likes of Scarlett Johansson for the part has had its perks: Mara has already appeared on the covers of Vogue and EW and should become an international superstar by the time the ball drops on New Year's Eve.

Upcoming projects: An untitled film from director Terrence Malick as well as possible 'Dragon Tattoo' sequels.