Global revenues from social media are projected to hit $16.9 billion in 2012, a 43.1% jump over the previous year, according to Gartner.

The bulk of that will come from advertising, which will contribute $8.8 billion. Social gaming revenue is next at $6.2 billion and subscriptions account for another $278 million. The researcher predicts “moderate growth” for the segment in coming years, though Gartner declined to share specific figures.

The advertising figure appears to be in line with a similar projection by eMarketer, which predicts $7.7 billion in social media ad revenues for 2012 and $11.9 billion by 2014. The U.S.’s share of such revenues will stay at around 53% over the next couple of years, according to eMarketer, which does not have an aggregate figure for social media revenues.

the Interactive Advertising Bureau estimates that global ad revenues for Internet advertising were $31 billion in 2011. Display ads accounted for $11.8 billion. The IAB didn’t break out figures for social media advertising.