|XP is just a number|
The whole "only a moron would use Windows" type of attitude wears pretty thin, and often hurts the cause of Open Source. Even advocates of one particular OS (or language, or app) may have to choose an alternative, because that was the best choice at the time. When money and jobs (including your own) are on the line, you have to choose whatever works best, even if it's only better because a certain company holds an illegal monopoly. Yeah it might suck, but can't always be fixed, so you just have to work around it.
This is the kind of paragraph that makes me feel proud about our profession. It clearly shows wisdom when talking about software and takes away the horrible stereotype that OSS advocates are some kind of barbarian horde that trashes around anything that even looks like a commercial software.
One personal experience I can share with you is about the International Free Software Forum (which it's 7th edition will take place here in Brazil in a couple of weeks, with YAPC::Brasil::2006 as a part of it - read more here).
I first attended the Forum last year and before I went I've heard all sorts of stories about people being thrown out the meetings because they were advocating windows and such.
The difference between what I've heard and what I've actually saw was huge. The feeling of this kind of meeting is extremely friendly and people share knowledge and simpathy all around (ouch, again excuse my rusty english).
That's why I believe that taking away this kind of stereotypes - just as Mutant did - is vital for our survival as Open Source Developers.