Check out the big brain on Brad! And "Brad," in this case, is the BackMyBook guys who created this site (but you already knew that). Some new features just rolled out, including a nice little tool to let you know which of your fellow Junkies are online. See the image in the upper right-hand corner, where you log in? A new link there tells you how many registered Junkies are online. It doesn't represent how many people are on the site in total, just the registered users. Cool, no?
You can also now make "user comments" directly to a fellow Junkie. If you're going to say "howdy" to each other, or get into a side conversation with many back-and-forth responses, this is a great way to do it. So, if you're trading comments on a blog post and those comments go off-topic, consider taking the conversation "offline" in this way -- you still get to talk about that new pair of curly-toed shoes, and the rest of the Junkies can focus on the topic at hand.