Are computer games harmful to a child's development, or do they help train him for a future in computers?

Some are. Many computer games involve killing and maiming and seem to me to teach that violence is O.K. Others, like e.g. Snow boarding, teach dexterity and computer savvy. Like everything in life, it should be balanced by thoughtful restriction. I believe that the constant use of electronic gadgets is harming kids because it is surprisingly addictive.
Limit and monitor. The american academy of pediatrics recommends limiting media/ technology time to a maximum of two hours/day, (none before age 2) and none in a child's bedroom.This promotes physical activity and reduces the chance of obesity and sleep issues. Also, it promotes children's mental and social development through interactive imaginitive play, thus improving problem-solving, language and social skills.