Though the NPD Group doesn't include digital game sales in its monthly reports, it does address them in its latest survey, Game Purchase Drivers 2010. The study concluded that, when including mobile and casual games, an average of 71 percent of all games purchased during the last three months were physical boxed products, while the remaining 29 percent were digital purchases.

　　Of digital purchasers, 47 percent bought games from either casual-game portals like Big Fish Games or from digital delivery hubs, such as Steam. Some 42 percent of digital game buyers used app stores or cell phone carriers. Just 30 percent bought games from console services, such as Xbox Live, the PlayStation Network, or the Wii Shop Channel.

　　Another statistic uncovered by the study was that one in five gamers bought game add-ons of some sort during the last three months. Also, of the 3,704 people surveyed aged 2 and over, game buyers bought an average of 3.1 games over the past three months, including games for other people. (Children under 13 had their responses relayed by a parent.) Nearly 10 percent of purchases were funded by game trade-ins.