Hmmmm. I think you can know other people well online, but it depends on the context. I think Livejournal adds an extra layer of intimacy because of its filtering system - you can closely control who reads each non-public entry. As a result there are more postings about personal issues and the comments conversations become much more chatty and informal.

Of course, most people with whom I interact on LJ are merely friendly aquaintances. But there are a couple of people whom I’ve met through LJ and whom I consider good friends, even though we’ve only met in person once or twice. And there are several more whom I definitely think of as friends even though we’ve never met in person at all. I have never once been surprised or shocked when meeting an online chum for the first time in real life - to a woman, they’ve all been exactly what I was expecting. A few of my LJ and Chicklit.com friends have come and stayed in my house (one brought her baby to visit us on her second visit), and the only funny thing has been explaining to my real life friends how exactly my visitor and I know each other. And while the majority of my online friends are English or North American, a few from have become genuinely good real life friends too.

An online friendly aquaintance of mine was killed by a hit and run driver a year ago. I’d met up with him once in London and just before he died last June we had been making plans to meet up again, this time with a bunch of other LJ mutual friends when I went to London in July. He wasn’t one of my closest online friends, and I was almost surprised by how upset I was when I heard about his accident and, some time later, his death, because we’d only actually met once. But he was someone I’d always liked and admired very much, and we got on well, and so I felt genuine grief at his death.

To answer that, I think we can know people pretty well via this medium, save for cases where people are being dishonest or false, that might be easier for a lot of people to carry off over this medium than in person. There are differences in the qualities you would gain from an acquaintance in person than an acquaintance over the internet but certainly in terms of pure magnitude I think you could validly feel the same sense of loss for an acquaintance you had only interacted with online.

Again though, I don’t think this was the case with Di, or Anna (in the majority) on myspace, both of whom’s stories involved people who had never interacted with them beyond a one way flow of information about the object person’s life to the people grieving. This is a real phenomonon I believe, whether you call it recreational grieving or mourning sickness…