"A piece of personal information is worth about 0.1 yuan; suppose a risk investor is involved, at the highest time, the share price of a registered user could even exceed 10 US dollars ..." Yesterday, our newspaper published "Viral Marketing Specializes in Stealing Contacts: Social Networking Sites Selling Friends?", which immediately caught the attention of many netizens. Some industry insiders even introduced to the reporter some of the websites that adopt "viral marketing" techniques.