Operation Early Bird. It features various coordinates around the country counting down to theaters showing early screenings of the 6 minute prologue on the 13th of the month.The prologue for the movie is showing on IMAX screens in front of Mission: Impossible - Ghost Protocol. Other rumors suggest a new trailer is coming later today but nothing really to confirm this yet but we shall see!
The movies official website has also launched at thedarkknightrises.com and features a sound bite with a woman repeating several numbers. As I know more so will you!