LA Times is reporting that park spokesmen are saying that the fall appears to be accidental: http://latimesblogs.latimes.com/lanow/2011/08/yosemite-hiker-death-victim-identified.html

I read the eyewitness's horrific accounts. Since they only saw the fall from below, I wonder if they will have anything to add about whether this fall was self-inflicted. It sounds like the suicide theory may have been given to them by the SAR folks. Regardless, what an awful thing to watch. I understand why they gave up their climb.

Brent N