In 2011, Facebook (NASDAQ:FB) had virtually zero mobile Internet ad revenue. And in 2013? eMarketer expects Facebook to capture a whopping 12.9% of the revenue in the global Internet ad market, with mobile ad revenue up 333% from its 2012 earnings. Talk about a meteoric gain. But is the major growth over? Definitely not.

According to eMarketer's recent report, it's pretty clear that Facebook will continue to rise as an important beneficiary of bolstering growth in mobile ad spending. The report helps Facebook investors find meaningful context, and make more useful estimates about what's to come.

Facebook wins big on mobile
First and foremost, the report confirms that Facebook is doing very well on mobile. How well? eMarketer's year-over-year growth estimate for total worldwide Internet ad revenues in 2013 is about 80%, which pales in comparison to the 333% estimated gain for Facebook.

This is especially impressive because Facebook's mobile business already accounted for a significant percentage of its revenue in 2012. According to eMarketer's estimate, mobile advertising accounted for about 11% of Facebook's total digital ad revenues in 2012. Similarly, Google's (NASDAQ:GOOGL) mobile advertising represented about 14% of its ad revenues. Yet, eMarketer estimates that Google's mobile advertising will grow by just 92.1% in 2013 -- far less than the 333% growth predicted for Facebook.

There's no denying it. Facebook has excelled at monetizing its mobile platform.

What to expect in 2014
Google will dominate the world of mobile ads, yet again, in 2013, increasing annual revenues from $4.61 billion in 2012, to $8.85 billion in 2013, according to eMarketer. Facebook, the report forecasts, will only earn $2.04 million in mobile ad revenue in 2013. But if eMarketer's forecast is accurate, Facebook's mobile income will equal about 35% of its total worldwide ad revenue in 2013, up substantially from just 11% of total ad revenue the year before. Meanwhile, Google's mobile ad earnings would grow from 14% of revenue, to just 22.7% of revenue.

Clearly, between the 333% growth of Facebook's mobile ad revenues last year, and its increased mobile ad revenue as a percentage of total ad sales, Facebook looks set to benefit from another year of enormous growth in mobile ad revenue. Looking at these numbers, triple-digit expectations for 2014 seem realistic, and could possibly climb as high as 150%.

A sweet lullaby
As individuals across the world increasingly access the Internet through mobile devices, Facebook investors can sleep well at night knowing the company has caught up and is now doing extraordinarily well in this market. Facebook's rapid rise in mobile ad revenue has locked the company in position as a major player for the foreseeable future.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.