Well, video games are a catch all boogieman, and in the media for that reason all the time. It's not surprising that it's being tapped for marketing purposes.
What's more it's a conveinent scapegoat for bad parenting, or you know... kids acting like kids. The kid is unreasonable? OMG! Stop the presses, that absolutly *NEVER* happens, it must be the video games. Bad parents can point to video games making their jobs harder as an excuse.
I'll also say that the oft-quoted arguements about kids not going out to play as much as they should, have little to do with video games keeping them indoors. The truth be told, kids really can't go out to play anymore, and I think society has had a hard time really coming to grips with the results of the things leading up to it.
Simply put most areas have rules about unattended roaming children, largely because people don't want kids going through their yards and getting into trouble, especially when they could be liable for an accident on their property. Playgrounds again require adult supervision, as if something happens to a kid there the owner (even if it's the town) can be found liable.
Right now with pretty much the entire first world being based around the idea of TWO working parents and nobody doing child-rearing full time, you wind up with latchkey kids, and a lot of exhausted parents who can't do their job very well, and likewise can't exactly go following their kids around to keep an eye on them.
For some reason people seem to have this vision in their mind of the past, and American shows like "Dennis The Menace" with mischeivious children running through the neighborhoods having all kinds of "adventures" and such. Well, that's no longer the case, that has been slowly legislated away. Right now if your 10 year old is found a mile away from your house at a playground you could get in trouble for neglect. 30 or 40 years ago, that might not have been seen as quite as big a deal.
Of course the problem is also compounded by all the freaks we let run around nowadays, precedent over the decades has made society a lot more dangerous. The requirements for proof that have been built up mean that we have a lot more criminals like drug dealers and such running around, and they do target children, or tend to be indiscriminate when they go at it with each other. Two gang bangers throwing down over school drug turf are unlikely to care much if some kid on the monkey bars takes a cap through the head. This is to say nothing of the sex freaks, decades ago if you had wierd people lurking around it was dealt with in short order, today you really can't do much unless you have proof of wrongdoing, which is entirely reactive. Fair from a civil liberties perspective, but it does mean your kids are a lot less safe walking the streets.
It's not a nice situation, and these kinds of societal problems have no easy solutions. You might decide to loosen the rules for pursueing criminals for example, and you'd get rid of those wierdos, but probably more than a few innocent people would be harassed as well as one example. Public safety vs. civil liberties is a long standing conflict within society.
The point being that you can't even blame video games for kids not going out, and/or a decrease in physical fitness deriving from it. Of course video games are a MUCH easier target than someone saying we need to dial back civil liberties, or change local laws in ways that mean that property owners will have to worry about kids tromping through their yards and such without much in the way of recourse. In general we got to this point, because results like having kids stuck indoors so much has been viewed as a lesser evil compared to the things that would have to be done to ensure that an unattended ten year old can roam a neighborhood in safety, and without the danger of penelties being brought back on parents for things like tresspass, or the accidental destruction of property ( "OMG! the kid lost control of that wagon and it went through my flowers. It cost me hundreds of dollars to set them up like that, I demand reimbursement!..." not a totally ridiculous complaint if they are your flowers honestly, but still something parents aren't going to want to pay, and kids being kids accidents and stuff are going to happen.... see how we got here?).
