What makes a Web 2.0 Portal such as a social network successful? Ultimately, it's about content, relevance, zest of the founder(s) for the topic, and the ability to keep the site fresh. Of course, these are subjective criteria. Given two equally well-managed social networks targeting the same audience, are there some structural characteristics that make one site more successful than the other? A good place to start would to gain an understanding of the structure of successful Web 2.0 portals.
