I’m going to get right to the topic:
Consider starting a forum and/or community.
Disqus, can take care of this for you, but you can also use Reddit, for this, or even a free form host. This is something I’ve thought of doing if I ever decide to start a niche blog. There used to be a service called MyBlogLog that let anyone start a community for their blog. Yahoo bought it and shut it down a while later. Even though I’d like to do this, I’m not sure I’d have enough content. However, someone that writes a blog for more than just pleasure might. There used to be this thing called “a tiny thread,” and it was this thing where you could just start a conversation and the topic and all of it’s comments would show up on the site publicly.