Here's more on that civic engagement thing that may be most interesting to parents concerned about their gamer kids turning into vegetables (or kids arguing with their parents for more game time):

Neither the frequency of game play nor the amount of time young people spend playing games is significantly related to most of the civic and political outcomes that we examined -- following politics, persuading others how to vote, contributing to charities, volunteering, or staying informed about politics and current events. There is little evidence to support the concern that playing video games promotes behaviors or attitudes that undermine civic commitments and behaviors. At the same time, there is little evidence to support the idea that playing video games, in general, is associated with a vibrant civic or political life. The frequency of gaming was related to only two civic and political outcomes -- political interest and protesting--with differences only emerging between the highest and lowest frequency of game play.

Here are a few other interesting findings in the report, which was based on a national random digit dial telephone survey of 1,102 12- to 17-year-olds, and a parent or guardian, conducted between Nov. 1, 2007, and Feb. 5, 2008 (you can find the whole survey and plenty of related materials here):

97 percent of teens in the study play computer, Web, portable, or console games;

50 percent played "yesterday."
86 percent play on a console like the Xbox, PlayStation, or Wii.
73 percent play on a desktop or a laptop computer.
60 percent use a portable gaming device.
48 percent use a cellphone or handheld organizer.
60 percent own three or four devices from the above categories.
14 percent own zero or one device.

The report covers the popularity of games. Here are the top five, based on the number of time a game was mentioned in response to "What are your current top three favorite games?": "Guitar Hero" (158 mentions), "Halo 3" (104), "Madden NFL" (77), "Solitaire" (65), and "Dance Dance Revolution" (60). "[B]oys are more likely than girls to report playing ... violent M-rated games."

Game genres in order of popularity (percent of teens who reported playing a genre):

Racing ("NASCAR," "Mario Kart," "Burnout"), 74.
Puzzle ("Bejeweled," "Tetris," "Solitaire"), 72.
Sports ("Madden," "FIFA," "Tony Hawk"), 68.
Action ("Grand Theft Auto," "Devil May Cry," "Ratchet and Clank"), 67.
Adventure ("Legend of Zelda," "Tomb Raider"), 66.
Rhythm ("Guitar Hero," "Dance Dance Revolution," "Lumines"), 61.
Strategy ("Civilization IV," "StarCraft," "Command and Conquer"), 59.
Simulation ("The Sims," "Rollercoaster Tycoon," "Ace Combat"), 49.
Fighting ("Tekken," "Super Smash Bros.," "Mortal Kombat"), 49.
First-Person Shooters ("Halo," "Counter-Strike," "Half-Life"), 47.
Role-Playing ("Final Fantasy," "Blue Dragon," "Knights of the Old Republic"), 36.
Survival Horror ("Resident Evil," "Silent Hill," "Condemned"), 32.
MMOGs ("World of Warcraft"), 21.
Virtual Worlds ("Second Life," "Gaia," "Habbo Hotel"), 10.