It is an analogy I use when delivering workshops because to me you can build houses and they have addresses...but that doesn't necessarily make for a great community.
Websites are like those newly built houses.....they need people to create communities.....need recreational areas for people to meet and share....for me that is the social media element.
Here is a graphic I use to show the social media town to non believers! Feel free to share...
More on Social Media is like building a new town can be found on these blog posts