I was on DL10 today (767-300ER), and as we were building speed to take off, a 10 foot long ceiling panel fell down over the left hand aisle in economy, just behind Economy Comfort. A flight attendant called the pilot to abort, but we were going too fast to stop. We continued our ascent, and once we got to 10,000 feet, the pilot and copilot each came out to ensure there was no external damage. They weren't able to fix it, but after contacting ATL, decided to continue flying to LHR. Luckily, we didn't lose pressure or have to return to ATL. The crew handled the situation very well, other than the pilot being a little too jovial while making a passenger announcement. I'm glad he's a better pilot than PR person. :-)