Social Networking Introduction / Guide

Looking for someone to write a guide on "Social Networking" and the impact of social networking on web sites, and how to use social networking to generate web site traffic. Content will be used in a book, so this is just a generalized introduction to social networking (what is is, who uses it, why), and in depth introduction and reivews of at least 10 major sites? such as facebook, digg, myspace, linkedin, friendfeed, orkut, twitter,? and others and should have an in depth introduction to the top social networking sites, features/functionality and comparison - essentially this guide should give the reader a good, comprehensive instroduction to social networking, descirption of the major social networking sites, features and functionality and how social networking can help a business or individual and thier web sites.? Should include a "review" style summary of each site, features, benefits of one over another, who they target for users, and of course how using social netowrking can generate web site traffic. Expand to include all benefits of why businesses may want to have social netowrking sites for the business, employees, etc and how this can in turn generate business.? Shoudl include in depth information on social bookmarking, promoting your web site on social networks, how your profile can generate traffic to your web site. Must be ORIGINAL content/writing.