Paulou has a point though (pre-Klansmen comment), and also there are two complicated issues concerning this:
Misogyny and audience
Until Paulou brought it up, I just read avatar's post and brushed by it. Usually I speak up if something bothers me, so now I'm bothered by the fact that I didn't speak up. Sure, I get the whole thing of this is a small, close forum, so it meets most of the requirements for "know your audience" but on the other hand, some of our forum members are women, and Paulou's right about the comment being irrelevant and misogynistic. I wouldn't want anyone to feel that this is anything other than a safe environment. That kind of comment isn't something we want to encourage (and, in my book, based on everything that has been happening in America since August 9th, not speaking up about something is just as bad as endorsement. I'm not gonna argue this point, if you disagree, fine, but I'm not debating that).
I get the whole thing of "hey, relax, it was a joke", but gosh, that's really too easy to fall back on as an excuse. It's subtle, but that very quickly becomes "my sense of humour is more important than you feeling comfortable".
When and how to speak up
Teague has a point, too. Paulou's initial comment was terse and brusque. It has sharp edges to it, you know? And while I agree with why Paulou didn't like avatar's post, I don't think the tone of the response was that wise. I've spent the past 7 months trying to have discussions with people (close friends and strangers) about important issues and problems, and fuck, even with a kid-gloves approach, people get fucking defensive when you call them out in any way whatsoever. And it's even worse when it comes as an attack. There's a better way to confront people about stuff.
Though, of course, this is further complicated by the fact that the whole "hey, let's have a discussion" thing. If you're too far along the "everyone's entitled to their opinions" thing, it often just ends up with people "agreeing to disagree" and continuing with less-than-non-shitty behaviour.
Disclaimer: if you dislike the tone of a post I make, re-read it in a North/East London accent until it sounds sufficiently playful