A whopping 90% of US 9-to-12-year-olds play online games, according to a just-released survey by M2 Research. Broken down by gender, 91% of tween boys and 93% of tween girls play games online, M2 says. The survey of 5,000 children and teens nationwide also found that Facebook is now the favorite Web site among boys 8-11 and girls 12-15 (Facebook’s minimum age is 13 – see this earlier post of mine for some experts’ views on U13 use). In other game-related findings, Nintendo is tops in the handheld gaming space, but – because of the iPhone, iPod Touch, and iPad – “Apple is becoming a significant player especially with girls,” M2 found. Sony’s PSP is much more popular with girls (70% use the Playstation Portable, compared to 44% of boys). As for favorite games, the big brands still top kids’ lists, but the study said their favorite games and sites do “change often.” At the time of the survey, girls’ top pick was games in the Mario Series (20% of girls said it was their favorite), while boys’ was Call of Duty: Modern Warfare (36% of teen boys).