In my opinion, if he is doing well in all other areas and is not being disruptive at home, isn't staying out late etc, I say keep on doing what you have been doing. It's a sensitive time for kids, any drastic changes now will have wondering what he's done wrong. Let him have the time he has left to enjoy being a kid. He'll be out there earning a living soon enough.
On the other hand if he is being disruptive, not doing his chores, staying out late, then it is time to draw in the reigns, lay down the law, and set some more ground rules. Everybody, even adults, are into video games and web journals and blogs. If you're like me, you'll want to take care of any chores in order to have your time at the computer and enjoy it without feeling guilty about something you should be taking care of. Encourage your son to do the same thing and, so long as everything else is taken care of first, let him have his time on the computer.
You're husband isn't wrong, he is simply preparing for when he has to push his son to get a job and get out into the big real world. Talk, negotiate and compromise. And discuss it with your son also, all in preparation for what his next step will be. Try to avoid letting him hear you and your husband arguing about him and his future, he'll hate that and it will make him feel very guilty.