update on Saturday, Apr 17, 2010: More information about how her death was preventable here: http://www.hindu.com/2010/04/17/stories/2010041756041600.htm
According to a YouTube video posted by AlJazeeraEnglish on November 3, 2007, former Pakistan Prime Minister, Benazir Bhutto, stated in an interview that Omar Sheikh murdered Osama Bin Laden. It occurs at 6:10 into the video. It's interesting to note that during the interview she was not corrected by the journalist. According to the US Government Bin Laden is still alive. I say this because Bin Laden is still on the FBI's Top Ten Wanted List. Obviously there is an error somewhere. Either Bhutto made a mistake in her statement and the media that published the video didn't notice or Bin Laden is dead and Bhutto was killed to silence her. Perhaps the truth is somewhere in between.