A little more research...

Virtual community:A virtual community is a social network of individuals who interact through specific media, potentially crossing geographical and political boundaries in order to pursue mutual interests or goals. One of the most pervasive types of virtual community include social networking services, which consist of various online communities.

Virtual communities are used for a variety of social and professional groups. It does not necessarily mean that there is a strong bond among the members, although Howard Rheingold, author of the book of the same name, mentions that virtual communities form "when people carry on public discussions long enough, with sufficient human feeling, to form webs of personal relationships".