The latest trend in social media advertising is to employ user engagement and advocacy within advertising products. Facebook used Likes to power ads, and now Google is following suite.
Google announced that it would use users’ names, photos, ratings and comments within advertisements to endorse marketers' products.
Endorsement ads use semi-personal information that users acquiesce to social networks in exchange for the use of platforms. Google changed it's terms of service to make way for the new advertising product, and it altered its search settings to make it more difficult for web users to avoid others on it's social applications. Google, Facebook and soon Twitter are using their vast troves of personal information in ways the authors did not expect when they originally posted it.
From an advertisers point of view, these new ad products replicate word-of-mouth marketing and, therefore, are far more effective. The social advertising industry is worth $9.5 billion dollars, but advertisers need to exercise caution that these ads don't destroy the trust built up previously between the social networks and their users.