Certainly kids are impressionable, and though most people are able to differentiate between virtual reality and real reality, there are always cases (in children and adults) where an individual may not be able to distinguish thought processes used for a game and thought processes used for real life. And certainly in movies as well, if every movie out there has casual sex and glorified violence, we can expect to see a shift in paradigms by an entire generation, not just a select few.
I still vehemently disagree with Dr. Phony... I mean Dr. Phil. Violent video games are not the source of all evil in today's world. Though I do find the gratuitous violence in some games today distasteful. Almost as distasteful, in fact, as the way that they are marketed. I have ground my teeth as I watched GTA commercials with cold-blooded murders and gunpoint bank robberies played to a cheery beach-boys-esque song. I find it disgusting.
But that's me.
What I think the real problem is traceable to is terrible parenting these days. The younger brother sees the older brother/father playing some game like GTA and enjoying it, so he emulates him. He comes to like the game and assume that its values are solid. That's not the game's fault, that's the fault of the parents. They don't educate their kids on right and wrong anymore, they leave it up to television and games.
I personally play RPGs mostly. Story is what buys me into a game, not how good the combat system is.
But, again, that's me.