I like the writer's breakdown, but all of this is common sense to me. It can all be boiled down to: (1) write good, engaging content and (2) respond promptly to readers' comments.
I agree that it is common sense but a little more than that:
1) Write good, engaging content with a strong point of view
2) respond promptly
3) Share your spotlight & traffic with your readers by reblogging the best comments and giving specific readers credit for the idea for your blog posts
4) As your readership grows, you cant respond to all comments so identify leaders to help you and ask for a couple of guest posts from them to make them feel a sense of ownership.
5) Prioritize responding to people who are commenting for the first time to welcome them to the community.