I'll try not to be callous, but fatalities have become rather common on the Half Dome cables -- she's lucky to have lived.
Just a week after her fall, there was a fatality -- first of the year, I believe.
http://www.mercurynews.com/breakingnews/ci_12589788
And three people died within a year (October 2006 to June 2007). Before then, it was rather rare to hear of fatalities.
There is a big warning sign -- but people generally get summit-fever and won't turn back when the goal is so close.