Could this be the year's most competitive category?
Rooney Mara, "The Social Network"
Pro: As Mark Zuckerberg's college girlfriend (at least the movie version of Zuckerberg) she is part of two key scenes which set up the entire film's conceit. She's also excellent (almost making you forget her turn in "A Nightmare on Elm Street"). She could benefit if the Academy members embrace "Network" in a big way.
Con: Her character is completely made up and "Network" ends up being much more about the boys than the girls.