Designer Kathy Sierra abruptly cancelled her appearance at the O'Reilly ETech conference here in San Diego this week, after receiving graphic and sexual death threats that made her afraid to leave her house, she wrote on her blog today.

She writes: "They posted a photo of a noose next to my head, and one of their members (posting as "Joey") commented "the only thing Kathy has to offer me is that noose in her neck size.""

Sierra adds:

The sort of language used against Sierra is outrageous, unacceptable, and, unfortunately, it's become normal on the Internet. Name-calling is routine, and death threats aren't particularly unusual. It's hard to read any public forum on the Internet without coming away wanting to wash your hands.

Internet users as a community need to take a stand on this one. We need to let Sierra know that she has our complete support, and we need to let the people writing these vile messages know that their behavior is simply unacceptable.

Moreover, the owners of the forums where these threats were made need to take a stand. They need to cooperate with police in investigating the threats, and help bring Sierra's attackers to justice.

Update 3/27: Locke and Sessum respond.

Locke writes: "[I]if Kathy Sierra was receiving "death threats" in anonymous comments to her blog, they did not come from me or, to the best of my knowledge, from anyone I know."

And Sessum writes, in a post titled "For the Record,": "It is terrible that someone has made death threats against Kathy Sierra. I hope that she pursues those individual(s) vigorously. I expect that she will use that same intense energy to exonerate those who did not make those threats."

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