We’ve seen how well the viral marketing for The Dark Knight was executed. The movie was the highest grossing film of 2008 and now sits at 3nd on the All Time Box Office Chart (under both of Cameron’s uber successful films), and for those of you who still didn’t notice, it raked in over 1 billion dollars when you add international box office receipts. TDK was already going to be a cash cow. It was the much-anticipated sequel to Batman Begins, which was done so well that the fans could count on a bigger, better sequel. So it certainly didn’t need more help than that to sell it. I think the news about the…