Now, I'm not equipped to perform a statistically valid sampling of all conference talks, but pervasive anecdotal evidence lends credence to this notion.
There are more, but I don't think I need to internet-sleuth the entire set of well-known Ruby / Web personalities to demonstrate the point: a base lack of professionalism abounds.
Even thirty more examples would not neccessarily mean Rubyists are "often" like this. There are tens of thousands of them.
If ruby-talk, #ruby-lang, ruby-core, and Ruby conference talks were typically littered with swearing, there'd be a point. As it is, it's a generalisation formed off the back of a handful of cases. Stereotyping, if you will.
I've been covering the news in the Ruby world for about 6 years now, almost full time. People are inventing these silly stereotypes as a way to discredit the language and it's users, it's not based in reality.
Postel's law (gently reformulated) is important when you have one-to-many communication. "be conservative in what you send, be liberal in what you accept".
Heh, I really liked the analogy with Postel's law, and I guess you're right. The main criticising I've received about the blog post has been about the swearing, so I guess I could skip that next time.