ComScore announced today the results of its global study into online gaming.

The study is showing the number of unique visitors to these sites to have reached almost 217 million worldwide, which is 17 per cent more than last year.

All sites that provide online or downloadable games were included in the research, gambling sites weren't. Gaming sites attracted 28 per cent of the total online population and the average online gamer visits a gaming site 9 times a month.

"The fact that these websites are pulling in over a quarter of the total worldwide Internet population shows what a global phenomenon gaming has become. The potential of the online gaming arena should be especially appealing for advertisers. ", said Bob Ivins, EVP and managing director of comScore Europe.

The largest site is Yahoo! Games, with 53 million unique visitors, followed by MSN Games with 40 million and Miniclip with 30. EA Games came in fourth, but it lost more than 30 per cent of its visitors compared the same period last year.