From a New York Times blog today:
The Bushes Depart | 12:56 p.m. The helicopter steps are folded up. The blade begins to rotate. The Obamas and Bidens are standing still, holding each other’s hands, as they watch the helicopter rev up. We now have lift-off; the Bushes have left the Capitol at 12:55 — almost half an hour ahead of time. The Obamas wave.
Meanwhile, former Vice-President Cheney begins his long, slow roll back to Wyoming.