The debate is growing. From today's NYT:
Gregory K. Brown, a specialist on suicide at the University of Pennsylvania, said that public humiliation could play a role in suicide because “hopelessness is often a major risk factor, and if you’ve been publicly humiliated and your reputation has been tarnished forever, you could see how someone could become hopeless.” Such situations, he added, could contribute to feeling that life is unbearable.
And unlike some other forms of public humiliation, online insults can live in perpetuity. Whether that increases suicide risk, Mr. Brown said, is an open question, adding, “Although it’s plausible that’s the case, we know very little about the role of the Internet.”
See also this TechCrunch discussion: When Will We Have Our First Valleywag Suicide?