Jesse Eisenberg is perfect as Mark Zuckerberg, and I could barely believe that it was the same guy who was in Zombieland in this movie. Andrew Garfield, too, is perfect as Eduardo Saverin.
David Fincher's direction uses subtlety to it's most brilliant effect, and also the music supplies the final touch to this perfect film. Aaron Sorkin's script is highly intelligent, riveting and intriguing. Go see it, it's the movie of the year!