I quickly lost motivation to keep writing for my own site in part because the comments on my LW posts were of much higher quality than the comments on my posts for my own site.
It's handy to discuss things with people who (mostly) share a large amount of method and background knowledge. You can start conversations at a fairly high level, instead of having to explain over and over again the basics of probability theory or what truth is.
Recently I asked "What bothers you about Less Wrong?". It might be worth going back and checking out what people had to say, to see if there's something you can do to make Less Wrong more fun for everyone. (A few people made cool posts in response to complaints about lack of technical discussion, for instance.)
Let's hear the other side. What is cool about Less Wrong? What drew you in, what makes you stay, what makes you obsessively read every comment of every post? Is they're something we're doing right that we should be doing more? Bonus points for pointing out how we can make our awesome traits even more awesome, or how to make our awesomeness more obvious to outside folk who'd appreciate it. Whatever it is, add it to the comments.