According to NBC News:
An American Airlines flight from San Francisco to Dallas made an emergency landing at SFO after panels inside the plane's cabin began to come apart in mid-air, the airline confirmed Monday afternoon.
AA Flight 2293 landed without incident at about 2:15 p.m., an hour after takeoff, and taxied to the gate, according to FAA spokesperson Ian Gregor.
The plane's captain decided to return to San Francisco "after several interior wall panels came loose while in the air," American Airlines spokesman Matt Miller said.
That's exactly what you want to see when you're at 30,000 feet: the walls of the plane starting to come apart.
I can't imagine that feeling.
Here are some pictures from passenger James Wilson: