Social Networking or Online Community?

While I'm on the subject of social networking, Denis Pombriant at Beagle Research Group, a CRM consultancy, offers a thoughtful view on the topic. He concludes that,

Where social networking techniques can help best, I think, is in bringing together virtual communities of interest, people who will share their ideas about products and especially about their needs and attitudes.  Using social networking this way has several advantages over using it to simply get a deal.  By using social networking within a community you have the opportunity to test ideas with users and see how they react.  The information you collect can then go into better product designs or whole new products.  Social networking can also be used to test and validate marketing ideas, Web site design and the like. 

Perhaps, then, it's best to focus more on the social networking methodology than on social networking technology (a distinction Pombriant makes). Can you achieve the same purpose with an online community, perhaps with forums, on your own website?  Social networking is one tactic for creating a virtual community of interest, but not the only one.