First off, thank you for the link, it's pretty informative, and I appreciate it.
However, I want to ask you a question about the part I quoted. Does it matter what was actually said? Specifically, while we don't know the exact words, reading through both Adria's post and the guy's response, it's pretty clear that the joke wasn't actually aimed at someone in particular. (The "forking" comment, which he claims wasn't intended to be an innuendo at all but an appreciative comment, was actually directed at a male speaker.) So, since it was just "a joke about sex" and not "a sexist joke about someone", does that change your mind? (For discussion purposes, assume that there's no argument about whether the joke was directed at someone or not.)
To me? No. It doesn't matter if it's directed at someone in particular, or if it's just a general comment. See, the problem isn't what people say, it's the general attitude behind it. Traditionally male industries, like computers and video games and RPGs, are rampant with sexism and misogynistic behaviour, even to the point where it's implicit that certain behaviours are acceptable from men whereas they are not from women (including jokes about sex); inappropriate comments shouldn't need to be directed at anyone in particular to be called out as inappropriate. This isn't even touching the fact that it was a professional gathering, and commenting about sex in any respect is opening yourself to harrassment accusations.
As for the prevalent behaviour, let me give you a personal example: I'm a pretty avid gamer, both console and PC. Back before Christmas, I went to the electronics section of Wal-Mart to buy a currency card for the PlayStation store. The card wouldn't swipe properly to ring up, and the clerk (who was very apologetic but had a hard time looking me in the eyes) had to call in a manager to fix it. The CSM didn't look at me once, didn't apologize, didn't even address me at all. Instead, he addressed my seven-year-old son, who he assumed the card was for.
The attitude is even reinforced in areas you'd never expect. I love Big Bang Theory, but there was one episode in particular that really bothered me. The guys were on their way to a Star Trek convention, and the girls decided to give comic books a try. Now, the parts of nerdity I really enjoy (comics, video games, fantasy shows, etc) are typically male-dominated in the show, to the point where the guys, overhearing a fairly heated discussion the girls are having about the Hulk and Thor's Hammer, wonder if it's a new shade of nail polish they're discussing. Where the comic book shop has basement dwellers staring awkwardly at the girls in the shop. You laugh, because you think it's funny. Hell, I did too. But at the same time, it's enraging, because it's subtly reinforcing the idea that girls are out of place in a world of nerds and geeks, because they're pretty or they have boyfriends or they don't have some mental disorder -- the sole girl they showed at the comic book shop had social anxiety disorder, and she just wandered in to "get out of her comfort zone".
The attitude is everywhere. Everywhere. And people think it's normal. And that's wrong on so many levels, I can't even begin to count them.
To make a long story short, yes. Inappropriate comments are inappropriate, no matter who they appear to be directed at.