Social games are big, but who's spending money?

We all know by now that games built on top of social networks' platforms are a big deal, but the results of a study commissioned by games manufacturer PopCap give some idea of just what the numbers are like.

The survey estimates that there are about 100 million people in the United States and United Kingdom who play social games regularly, based on the 24 percent of survey respondents who identified themselves as such. More women than men--55 percent to 45 percent--identify themselves as social gamers, and the average age of a social gamer is 43. That's consistent with anecdotal reports that, in spite of social stigmas still attached to women and gaming, many of the most avid players of social games like Farmville, Pet Society, and Bejeweled are suburban moms.

Here's how the survey worked: Out of 5,000 survey respondents in the U.S. and U.K., 24 percent identified themselves as playing social games at least once per week for at least 15 minutes. Those users were identified as "social gamers," and it's their results that populate the rest of the survey. A PopCap representative said that while the study did include people under the age of 18, that "very few" in that demographic participated in the survey.

(Also note the fact that the survey was commissioned by a game publisher. It likely doesn't make the results suspect, but should be taken into consideration regardless.)

The rest of the survey has quite a bit to say about where people are playing social games, who they're playing with, and whether they're actually spending money.

Women who play social games are more likely than men to play with people whom they know in real life--68 percent versus 56 percent. And Facebook, unsurprisingly, has a huge lock on the market: 83 percent of social gamers say they play games on Facebook versus 24 percent on MySpace, 7 percent on Bebo, and 5 percent on Friendster. Keep in mind that this is U.S. and U.K. only: Friendster has more traction in Asia, and another social site, Hi5, is big in Latin American countries.

Companies hoping to cash in big on micropayments and virtual goods in games may be interested in this item, though: while just over half of social gamers (53 percent) say they have earned or spent virtual goods in a game, only 28 percent say they have spent real-world money on virtual goods and 32 percent have bought a virtual gift.

That means that many of the virtual goods in social games are still earned through the completion of offers and surveys rather than purchased upfront with real money. A full quarter of social gamers say they've been "misled" by an ad or offer in a game, a nod to the prevalence of companies that let players earn points toward virtual goods by completing offers or surveys. These third-party outlets became the subject of major scrutiny last fall when allegations surfaced that they were scamming users into actually spending more money--one of the leading companies in the space, Offerpal Media, ended up changing its terms of service and replacing its CEO amid the mess.

But the bad press didn't do much to alter the trajectory of the social games industry: right around the same time, Electronic Arts announced that it had acquired successful social gaming company Playfish for US$275 million.

This article was first published as a blog post on CNET News.