Organic vs Structured approach to community building, which works better?

Organic vs Structured approach to community building, which works better? Is it better to let the community decide the structure and purpose of the community, or should a structure be built which fits the model of the kind of community that you envision working best?

We will start the evening with 5 minutes talks from three new members/guests:

Paul Kamen (https://www.meetup.com/clswest/members/13960932/) - Host of various topical conferences on The WELL, one of the first social networking sites. Founded in 1985 by Stuart Brand (of Whole Earth Catalog) and Larry Brilliant. Vee Govender (http://regionalchange.ucdavis.edu/projects/current/labor-studies) - U.C. Davis Center for Regional Change, Labor Studies, author of "The dove on our avenue (http://bit.ly/o8mioy)" Nasimiyu (http://www.nasimiyudesigns.com/index.php?option=com_content&task=view&id=70&Itemid=89) - Nasimiyu Designs, focusing on jewelry and African fine art. Ten percent of purchase goes to Born to Aid, a non profit 501 (c) (3) foundation, supporting children in Kenya

Due to virtually no activity on CLSWest Idea Board (http://clswest.uservoice.com/) since May, this topic for the evening has been chosen.