The kids that go "postal" in their schools rarely (if ever, I've never heard of them saying that) point the finger at videogames. I've only ever heard various senators, psychologists, and other professional people blame videogames. It's an easy answer, and a cop out, and it's avoiding the real issue because no one is prepared to accept the responsibility of something like this. Not the parents, not the teachers, not the kids themselves, or the other kids that go to school. The way these events are covered it makes it seem like their school was the happiest place in the world and for some strange reason a couple of perfectly happy kids just decided to go nuts.
Society's problems, especially in the education section, go a lot deeper than some violent videogames. And there's a good chance they won't get coverage on any network news station...