Facebook has unveiled a new social metric that will detail the benefits of using social context for ads. The Ads Manager has a Social percent column that shows the percentage of ad impressions that were delivered with social endorsements.
This Social context is the part of an ad that shows a user who among his or her Facebook friends have liked or viewed a particular page, event or app. Marketers will be able to see the number of impressions that these ads deliver on the Reports Tab in the Facebook Ads Manager. All of this may give Facebook more leverage to prove the worth of social advertising, which is still considered an unproven experiment by some marketers
Source: Paid Content
