I think there are two problems here. First, I've no idea how old this person is. I actually asked, during the 'happy hacker' debarcle, for this very reason - I don't like the idea of youngsters being slated when perhaps they don't understand social boundaries and interaction the way adults are expected to. I was told, in not so many words, his/her age was nothing to do with me. Fair enough, but I'm not going to make the assumption that someone that rude simply must be a kid who can't be expected to know basic manners, and frankly anyone over 18 is an adult who really should know better.
Second, an apology would go an awfully long way. If one's been given I'm afraid I've missed it. If the person in question would hold their hands up and admit to posting in a seemingly arrogant, offensive and immature way then I would imagine the majority of people who are still upset would be more than happy to let it go. This person managed to insult a large proportion of this forum's community in one fell swoop.
As it stands, the person in question came onto a forum and posted obnoxious, arrogant and downright insulting threads, seemed to throw a strop when people bit back and weren't happy with what was said (understandable, surely), and even though an apology hasn't been forthcoming everyone's now expected to not just let it lie but also give advice to this person. In the real world, the person in question wouldn't be forgiven so quickly (without an apology, remember) and perhaps would learn that you simply can't go around lording it over people and being offensive without repercussions.
I've refrained from posting anything in the most recent, polite threads from this person. I won't snipe for the sake of it. But equally, had I gone onto a forum and posted the sort of things this person originally did, and failed to acknowledge I was being offensive or apologise, I certainly wouldn't then expect people to be falling over themselves to offer me advice or helpful info.