As a result, some sites are turning to a new strategy to keep their services "sticky" and their users satisfied: They're not just encouraging them to network online, but to attend offline events and parties in the real world as well. Yelp now regularly hosts parties in big cities around the country.

Now smaller start-ups are trying use the offline-online hybrid model to gain momentum against community heavyweights like Yelp and Meetup.

Recently relaunched Going, for example, is a "social-event calendar" that aggregates announcements, encourages members to network with each other online beforehand, and lets them maintain profiles with favorite events and photo galleries.

"The secret to Yelp bridging the online-offline gap is the reviews," Yelp user Adrian said. "Someone's writing can reveal a lot about that person, so before I meet a reviewer in real life, I have a general idea of who they are and what they are like. With Facebook, I might get an idea of what a person looks like, what movies and music they enjoy, but reading something (that) someone has put a piece of themselves into makes a complete difference."

http://news.com.com/Social+networks+geared+for+offline+success+-+page+2/2100-1038_3-6192780-2.html?tag=st.num

For social networking web is becoming an orchestration layer that allows people to identify potential friends and control the flow of social events in their lives. Very similar to what Dell, for example, did to PC manufacturing, Amazon to book shopping, and etc. Also, very relevant to the emerging click-to-brick model.