Addiction is a peculiar thing. Anything that makes you feel good is inherently addictive. People get addicted to biting their fingernails.
Is it bad to be addicted to reading? Or working out? If gaming is making your synapses fire faster, if for nothing more than to increase your IQ score (which is based on speed), is it a bad addiction?
Addiction is a compulsion to do something you would not chose to do. It really depends on that something whether it's good or bad for you. Addiction is something everyone will have to deal with at some point in life. Learning it from gaming is probably not a bad thing.