It seems pretty clear that our readers are overwhelmingly on Twitter — we've been exactly as slack about getting followers on Twitter as we have about getting people to read this little corner of the web, which is to say we've done nothing whatsoever beyond tweeting and posting occasionally.
Twitter is generally pretty entertaining and occasionally professionally interesting. For instance, over the last week, a couple of nice conferences have been basically live-tweeted.
But I haven't seen real progress on making it a more systematically useful tool. There's an effort afoot now that create a forum, #lingchat. It's just getting rolling, but could become an interesting forum.
Check it out.