Audience vs. community

Today, I thought about one of the questions that was posed on the discussion board about building successful communities.  Shirky states elements such as sharing common interests, good communication, and good timing helps build communities...but I was curious what else helps build a good community?  I ran across this blog http://www.therisetothetop.com/davids-blog/12-keys-building-online-community/ and it talks about how to build a community and not just an audience.  An audience is not interactive.  I had not really thought about that distinction before, but it makes sense.  The blog also talks about being active on social media, making your content shareable, asking and answering questions, and so on.  I believe it's an interesting read...