Quick: What’s the most popular type of video game? If you answered “shooters,” “sports,” or “casual games,” you’re wrong.

It’s actually “action” games, according to the NPD group, the official tracker of U.S. video games sales. And you might be surprised to learn that the most popular genres can change with the tide of release calendars.

“Genres move up and down the ranks largely on the shoulders of one or two big games in any particular year,” explains NPD analyst Anita Frazier. “In 2008, that game was Grand Theft Auto IV.” (see graph)

Some genres, like the aforementioned action, are easier to classify than others. You’re either engaged in a Hollywood-style plot and getting into fisticuffs or you’re not. But other top genres aren’t as easy to define, and many of the games boosting their popularity are titles that seasoned players take least seriously. Think you know what constitutes a “sports,” “strategy,” or “adventure” game? Think again. Continue reading…