Many of the replies here goes along the lines of: "Time spent gaming is time lost doing sports, helping elders, reading books, socially interacting face to face."
So these kids "hanging out" in the malls; better or worse than joining a raid online? What about the 3 meatbags spread out on the floor in front of the TV watching Nth season of American Idol. Is that so very healthy?
Yes, sports is healthy. Yes, talking face to face is healthy, but using your brains during gaming is also healthy. Nothing is healthy to spend too much time on. Nothing!
Kids today socially interact face-to-face all day at school. If you want to worry, worry about all the elder people that don't understand online communities (games, social websites...) and haven't spoken to anyone for the last 6 days.