He'll step down as CEO in 2015 and leave the Mouse House entirely in 2016 at the age of 65. As part of the transition, reports the WSJ, Iger will add the position of chairman in March 2012 (current chairman John Pepper will be leaving at that time). From the Journal:
The company said a successor had not been chosen. But Mr. Iger for several years has been grooming a group of potential heirs, moving senior managers between jobs to broaden their experience and to help assess which among them has the right combination of skills for the top job.