On his last day in office on Thursday, Pope Benedict XVI offered a final blessing to his cardinals, and pledged his loyalty to the new pope—whoever that may be. Benedict began the day by delivering a short personal message to those Roman Catholic cardinals who have already gathered in Rome for the upcoming conclave to pick his successor. After closing with a brief prayer, he then took the time to shake hands and speak individually with the more than 100 cardinals who gathered in the Clementine Hall. They also kissed the papal ring that will be destroyed after Benedict formally steps down. 

Later today, he will take a helicopter to Castel Gandolfo, a Vatican summer retreat that will be his temporary home until a permanent residence is set up in the Vatican. After arriving, he will do one last "balcony greeting," waving to assembled faithful in his appearance in public as the Pope. Then at 8:00 p.m. local time (2:00 p.m. Eastern in the U.S.), his Swiss Guard will leave the castle and close the doors behind them, officially ending his papacy and making Benedict the "pope emeritus."

In order to dispel any doubts about who Roman Catholics should put their trust in now, Benedict told the cardinals he would give "unconditional reverence and obedience" to his successor—who was likely sitting among them—and that they should act "like an orchestra" supporting the new Pontiff as one united body.   

Update (11:06 a.m.) Benedict is on his helicopter right now, leaving the Vatican for the final time as Pope. Bells are ringing out across Rome as he flies away.

And here's his last tweet, send just before liftoff.

Here he is taking one last look at the Coliseum. He is not flying the copter, even though he apparently could have.

11:37 a.m.: Here's a nice shot of Castel Gandolfo, the Pope's new (temporary) home. He just arrived a few moments ago.

The pope is now addressing the assembled crowd, his last public appearance. "I am just a pilgrim ending his pilgrimage on this Earth." After one final blessing, he went back inside. In just about two more hours (8:00 p.m. local time), his papacy will officially end.