Direkshun's being kind of a pain in the ass about it ("spreading more death"? Really?), but he's got a point. There are different levels of effectiveness of firearms, firearm accessories, and ammunition, and a major part of the gun control debate is predicated on where to draw the line between which are regulated, controlled, or outright forbidden, and which are not. We already have much of that in place: fully automatic weapons require the class 3, while semi-autos do not. It's the same thing, it's just a matter of where to draw that line.
As for fully automatic weapons, CrazyPhuD, you have a point - sort of. Full-autos are used like that in the military, and inexperienced users would have a good chance of finding themselves suddenly out of ammo a lot. Imagine, though, if the Batman shooter guy had had one - with the darkness and chaos and closely-packed victims, he would have increased his casualty list by quite a bit. I think automatic weapons are regulated just fine the way they are - with the super-stringent restrictions that, by the way, are very effective in keeping them largely out of the hands of criminals.
I have to go to work today, but I'll check this thread when I can.