Of the 117 million active gamers in the U.S., 56 percent play games online. Sixty-four percent of those online gamers are female, according to results of the survey, released by Nielsen Entertainment on Thursday.

The survey defined active gamers as those who are 13 years or older, own at least one game device, and play at least one hour of video games a week. Game devices include game consoles, personal computers and handhelds. Nielsen surveyed 2,200 active gamers online in July.

"The expansion of next-generation hardware and technology in the marketplace is simultaneously delivering new ecosystems of social exchange, interactive entertainment, media experiences and advertising models," Emily Della Maggiora, a senior vice president of Nielsen Interactive Entertainment, said in a statement.

The survey found that while the casual game segment is growing, casual gamers tend to jump from one free demo to another with little sense of brand loyalty. While banner advertising provides a good revenue stream for the online game providers, gaining brand loyalty and getting people to spend money for subscriptions or downloads will be the key to growing the market, Nielsen researchers found.

Currently, casual gamers spend ?9 a month on games. Those playing multiplayer online role-playing games spend an average of ?26 a month, while Microsoft Xbox 360 gamers spend ?35 a month, the survey found.

Among game console owners, the majority own more than one device or platform--including PCs--for playing video games. Fifty-nine percent own a Sony PlayStation 2. Microsoft was next, with 33 percent owning an Xbox. (Fifteen percent of all active gamers own an Xbox 360, while about 8 percent of active gamers own both an Xbox and an Xbox 360.) Nintendo?s GameCube came in third at 30 percent.

Twenty-four percent of active gamers also played on cell phones. Personal computers, however, dominated as the platform of choice.

Sixty-four percent of those who regularly played video games, played on PC-based systems. Just two years ago, according to the Nielsen report, many game industry analysts wondered whether computers would be able to compete with game consoles and handhelds.

Playing video games is also becoming more of a contact sport--sort of. The average gamer spends five hours a week playing games with other people online, while teen gamers spend up to seven hours a week.

[via Cnet.com]