snippy posted some musings (I am linking to the LJ post rather than the DW post because more of the comments are there) about why her LJ friends list is so much quieter than it used to be and about which places on the Internet have felt like social communities to her. I posted some of the following as a comment.
My LJ flist is quieter, but partly because during my family crisis last summer I cut my reading list way back. Also, I moved the folks cross-posting at DW to a different list.Where are your Internet meeting places? Have they changed over time?
When I got back enough time to want to read journals again, I went around subscribing to people on DW; there is something about the subscription/access model where I give myself permission to read the journals of people I don't know, whereas with LJ's friends list model I want to wait to be invited.
I'm not deeply into media fandom or fanfic myself, but it seems to me that a number of the people who are also have interesting-to-me thoughts about other stuff.
I flounced to LJ during a week where my Usenet home alt.polyamory was being annoying. But I still post to both. My journaling home is now DW but I cross-post almost everything to LJ and have enough friends still here that I plan to continue. Usenet and journaling encourage very different sorts of conversations and I value both kinds.
Last year I got sucked into Facebook but at this point I've been spit out again and I only post fluff there for the most part. I sometimes post the same fluff to my journals but often no one comments in the journals and so I assume the stuff goes over better elsewhere and am less likely to make the effort to repost it in the future. (I tried auto-crossposting from LJ to Facebook and didn't like it.)