I think the main thing is that it looks like online conversation, but it isn't quite. Most of the time, I'm reading something that someone I care about posted to the world at large, and I can post a response to it but it's rather rare to get a response to the response -- unlike conversations where people really talk back and forth, these have a half-life of far less than one response-to-a-response.
Which means that, a lot of the time, there's no real sense that the response got read. Nor does it really lead to anything definable -- it's just a post, to the world to read.
I guess that much, though, is simply stating the very very obvious. The interesting bit is how I'm finding myself reacting to this.
My guess (based on having only been "here" for a week) is that when it works well, eventually what happens is that all of the unrelated posts start to fill in and become something coherent, sort of like forming a pointillistic painting one randomly-picked dot at a time. And so one gets to know people.
And, I suppose, in the process of responding to the posts made by people one cares about, and in turn having those people respond to one's own posts, there forms a large collection of back-and-forth responses that, although they're usually unrelated to each other, still end up covering the sort of ground that conversations cover in getting to know someone.
I guess what's feeling impersonal to me is that all of this is being done as audience-involving performance art, sort of. And, if someone says something that I care about, and I post a response to it, I usually will have no idea what they think of my response. Or if I post support, I usually have no idea if my support in particular mattered.
Maybe it's that I tend to think of relationships as dyadic sorts of things -- that is, as one-on-one sorts of things. Even in things that look like group relationships, I tend to process them as a cluster of dyads. In writing this, for example, I'm largely thinking of it (when it's not a me-and-blank-page without thinking of audience) in terms of one particular person on my friends-of list at a time.
Another piece, I think, is that I don't learn by listening, so much as I learn by talking. And that's also how I get to know people -- by talking to them about what they've said, and getting their reactions to what I say, and cycling that process for a while in conversation.
On the other hand, as it seems to me, this format for interactions doesn't work that way. Instead of assembling group interactions out of lots of dyadic pairs, it requires in-channel dyadic sorts of things to generally happen in essentially the interference patterns of the one-to-group interactions.
And it also has the interesting twist that I can't get to know people by follow-ups to their livejournals, and I certainly can't find out (to any appreciable extent) whether they want to talk to me by doing that. And, in particular, there's no format for asking questions of someone in particular; the thread lifetimes that I've seen seem to preclude doing that in-thread as a useful type of interaction. I have to get to know people by posting things to the world in mine, and reading responses from whoever posts -- which may or may not include the particular person I was wanting to get to know.
This, at best, is going to take a while to get used to, and to figure out where my own style of interaction fits into it (and how much of it fits).