It seems to me that it's less of a permitted invasion of privacy as it is a way to ramble, to throw out words and hope someone catches them. In any case, it's anyonymous.

I have a LiveJournal and haven't done anything with it yet: as much as I like to talk, I think that if I want someone to hear me, I'd be better off doing it in Chat or the Forum. Talking through an online journal is, to me, like saying that what you have to say isn't important or interesting enough to make it any more public. Most Rinkies seem to use it as a weblog, though. That works, too.