There was a lot of controversy around that hand. I think the official explanation from the floorman and supervisor was that as soon as the floorman said "one" the hand was dead. He said "hand dead" a second later, but the time was up when the said "one"....
I think this explanation is pretty thin. Friedman said "call" before the words "hand dead" were pronounced so he should have been allowed to make the call.
Here is a piece on Pokernews on the incident: http://www.pokernews.com/news/2010/09/the-wsop-on-espn-world-champions-november-niners-and-one-ver-8830.htm