If I were asked if violent video games caused more aggressive behavior in youth, I would say no. The controversy over the issue has led to the same number of studies saying they have a positive correlation as no correlation at all.
There are several flaws I find in common arguments for the former. Obviously one thing is that hostile behavior in children studied could be due to other external factors such as predisposed aggressive behavior or family troubles. Additional problems with some experiments is that they loosely define what "aggressive" acts are and tend to show short-term effects instead of long-term, which is what really matters.
Saying that the youth is becoming more violent due to media is a bold statement in itself. Juvenile crime has actually declined over the years while the gaming industry is increasing in popularity world-wide. Consider this data from the Office of Juvenile Justice and Delinquency Prevention. Juvenile Arrest Rates.xls
To also argue that they are becoming desensitized to violence through playing video games is also a stretch. For example, just because teenagers play Call of Duty does not mean that if they were to enter the army, they would be fine with the death of others encountered. Gamers recognize the difference between real life and fantasy. Overall, there is simply not sufficient or conclusive evidence to link violent video games with heightened aggression in teens.
If interested, here is a link for the most violent games of all time.