The problems of addiction is always with the addict rather than with the substance. Addictive personalities can obsess with the wierdest things. It's what happens in their brains which makes them want to repeat behaviours to their own detriment. Yeah, because the web is otherwise immediate and gratifying you will have addicted personalities become addicted to it to a point where it becomes a problem.

If you are merely using it to stay on top of your job or your interests and know when to put it aside, then you probably are not addicted to it and shouldn't have to worry. If you are an addictive personality (and you know who you are) see your doctor or a psych counselor about it; there are drugs that maybe can dampen the obsessive urges.