I saw that story when it aired locally here (I watch KGW news, as I consider them one of the best). I've always thought we should encourage concealed carry permits, and encourage or require additional training for people that may find themselves in situations like that. I believe it would reduce the body count in the long run.
Just think if 1 in 10, or even 1 in 20 had a concealed weapon and was properly trained on it's use in public shooting situations. In a crowd of 300+ (like the Colorado theater), or a mall with 10,000+ (Clackamas Town Center), look at how many people these nut jobs would have to face that could be shooting back. That would be a serious deterrent to future would be copy cats.
I would even go so far as requiring 1 or 2 anonymous people in each school (teacher, principle, or other faculty member), for places that don't have on campus security. The eye witness reports from the Connecticut school shooting said they heard gun shots for over ten minutes. In that amount of time, if someone were on campus and armed, they could have intervened.
Limiting clip sizes, or banning types of weapons is not a solution. It only takes a couple seconds to pop in a new clip. When no one is threatening them, they have all the time in the world.