He is a borderline sociopath, never smiling, never raising his voice, never conceding an argument, driven to create his masterpiece through the unforgettable pain of being dumped in the movie's opening scene. What perfect casting Eisenberg is. (I couldn't help remembering, incidentally, his character's disparagement of Facebook in the movie Zombieland: jeering at idiots with status updates like: "Limbering up for the weekend.") Sorkin gives everyone great lines. It's pretty much a non-stop fusillade of put-downs, insights and zingers. I wonder if the real-life Zuckerberg has ever physically said as many words as this in his entire life.