Game addiction a mental disorder?

The American Medical Association is trying to get "video game addiction" declared as an official recognized medical disorder. The study claims there's a negative impact caused by video games such as aggressive thoughts and aggressive behavior. Heavy game use is described as anybody playing over two hours a day, which means quite a lot of gamers would fall under this category if the AMA has its way.

1UP reports:

That cheerful tidbit comes to you today via a chain whose links include Kotaku and Spong and whose conclusion is this Google HTML approximation of the proposal in question. The submitting doctor is Dr. Mohamed K. Khan, MD, PhD and chair of the AMA's Council on Science and Public Health.

Dr. Kahn begins by citing prior research backing up the now-familiar claims of videogames' unsociable effects... especially on people under 10. For the purpose of the report, "heavy game use" is described as anybody playing "more than 2 hours a day." Games, continues the study, are strongly correlated with "negative actions such as aggressive thoughts and aggressive behaviors." "Not surprisingly", continues the report, "the video game industry's own research has concluded that there is no causal relationship between video game violence and aggression."

More details at 1UP (Note: this resource is no longer available).

Do you think two hours of gaming is problematic or therapeutic?