Dive summary:

• A Berg Insights study projects mobile ads will be 4.4% of the entire market by 2017.
• Mobile ads are currently about 1% of advertising dollars, and mobile advertising brought in about $5 billion in 2011.
• Berg expects mobile ads to be 15.5% of online advertising in 2017.

From the article:

… Of course, five years is a long ways out, and the track record on such long-term prognostication is mixed. But if Berg is right, that’s only good news to a company like Facebook which has found of its traffic and customers moving to mobile platforms but only recently began advertising on the phone.