Dive summary: 

• Advertisers gained a large amount of confidence in Facebook advertising in the past 15 months, according to a study from Ad Age. 
• Marketers have long been aware of the value in using Facebook's platform, with 80% consistently responding they use the network as a marketing channel, a major increase since Facebook launched its IPO 15 months ago. 
• Approximately 74% of respondents replied that their Facebook budgets now include ads, up from 62% in January 2012 and 54% in June of 2012. 

From the article: 

"Fifteen months has also made a crucial difference for Facebook and its resurgent stock price because of its mobile ad offering, which was nascent in June 2012. Mobile is now the main accelerant of Facebook's revenue growth -- with 41% of the company's ad revenue coming from advertising on mobile news feeds in the second quarter."