While I agree that this behavior is unacceptable, I do not think that it is special to Open Source conferences.
> A presenter had a title slide followed by a slide of bikini-clad women
> holding laptops, which he said was just to get people to pay attention.
> I'm not sure if we were supposed to pay attention to the women or to what
> he was saying though.
Yeah, a picture of bikini-clad men holding laptops would have been way funnier. ;)
I did not attend this, but I assume it was just a (bad and stupid) joke. I personally don't see anything sexist there.