eMarketer indicates that $220 million will be spent on ads in social games in 2010. This is a significant increase from the company’s estimate for the 2009 year, when ad spending was $183 million.

They expect that spending in the U.S. will increase 35 percent year-over-year to $192 million in 2011. International spending is expected to increase 33 percent over 2010 to $101 million, for a combined total of $293 million.

While many of the more popular titles on Facebook make much of their money from microtransactions, popular titles like FarmVille continue to attract advertiser attention.