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:

I do not want to be part of a culture -- the Blogosphere -- where this is considered acceptable. Where the price for being a blogger is kevlar-coated skin and daughters who are tough enough to not have their "widdy biddy sensibilities offended" when they see their own mother Photoshopped into nothing more than an objectified sexual orifice, possibly suffocated as part of some sexual fetish. (And of course all coming on the heels of more explicit threats).

I do not want to be part of a culture where this is done not by some random person, but by some of the most respected people in the tech blogging world. People linked to by A-listers like Doc Searls, a co-author of Chris Locke. I do not want to be part of a culture of such hypocrisy where Jeneane Sessum can be a prominent member of blogher, a speaker at industry conferences, an outspoken advocate for women's rights, and at the same time celebrate and encourage a site like meankids -- where objectification of women is taken to a level that makes plain old porn seem quaintly sweet.

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."

Searls provides a roundup of discussions around the blogosphere.