First, I want to say that a single article with evidence towards one side or another is never conclusive. People generally have a very poor idea of how research works, especially in the social sciences, but you generally have to be familiar with the entire body of research to really be able to make conclusions in context.

Disclaimer: I am not involved in psychology, and I am not particularly familiar with any of this literature. However, several people that I am close to are, and I have had several conversations about this with them.

My impression is that almost no serious developmental psychology researchers believe that violent video games have no negative effects on children. The nature and extent of those effects might not be widely agreed on, but everyone will agree that exposure to violence in video games and television has some kind of desensitization effect. Note that this is not necessarily the same thing as saying that they become more violent, but it's not exactly a positive outcome.

I won't bother trying to cite sources for all of this, as I've said, I'm not familiar enough with the literature to do it any kind of justice. But I will point you towards a meta-analysis published in 2001 that has been widely cited (though that's somewhat old, and I am not familiar with any potential new developments). Quoting from the abstract:

Research on exposure to television and movie violence suggests that playing violent video games will increase aggressive behavior. A meta-analytic review of the video-game research literature reveals that violent video games increase aggressive behavior in children and young adults. Experimental and non-experimental studies with males and females in laboratory and field settings support this conclusion. Analyses also reveal that exposure to violent video games increases physiological arousal and aggression-related thoughts and feelings. Playing violent video games also decreases prosocial behavior.