Despite the best efforts of Nintendo to turn gaming into a healthy pastime, the potential link between poor health and video games will be mined for countless years to come, with one such study claiming the negative effect of video games are more widespread than first thought.
Craig A. Anderson, PhD's article Violent Video Games: Myths, Facts, and Unanswered Questions was published in the American Psychology Association newsletter back in 2003 but is only just now gaining recognition from the gaming press, due to Anderson's use of his own studies as corroborating sources.
The report attempts to answer a number of myths surrounding the health impact of video games, with one choice quote responding to the 'myth' that the "effects of violent video games are trivially small":
Facts: Meta-analyses reveal that violent video game effect sizes are larger than the effect of second hand tobacco smoke on lung cancer, the effect of lead exposure to I.Q. scores in children, and calcium intake on bone mass. Furthermore, the fact that so many youths are exposed to such high levels of video game violence further increases the societal costs of this risk factor (Rosenthal, 1986)
Anderson's claim that passive smoking has a less widespread impact on lung cancer patients than violent video games do on the general population isn't surprising, though it is grossly uneven in its weighting.
For more nuggets of even-handed wisdom, you might want to read Violent Video Games: Myths, Facts, and Unanswered Questions. Do you agree or disagree with Dr. Anderson's thoughts?