Stricter gun control will solve nothing - anyone with a serious desire to kill people is going to do it. Firearms make it easier, but in many places, especially in the United States, it is a simple matter to acquire them legally or illegally. In short, making it tougher for law-abiding residents to obtain firearms is not going to reduce the amount of crimes committed by guns.
Conversely, however, some control over who is able to obtain firearms does need to be in place. Canada has a MUCH lower rate of death-by-firearm, suicide, homicide, or accident, than does the United States. The reason for this is two-fold:
1. Canada has a much less prominent gun culture, and Canadians in general are less likely to have an interest in firearms or own them.
2. Canada has a long history (even before the idiotic Firearms Act and its now-defunct registry) of taking a greater interest in who is able to own firearms legally. This does not curb illegal firearms possession. It DOES address three things:
A. The liklihood of unbalanced or dangerous individuals legally acquiring and possessing firearms is reduced. The Firearms Act has marked a drop in domestic violence using legally acquired firearms.
B. Improper storage or possession of firearms is limited; it results in fewer thefts of legal firearms.
C. Legal firearm owners are registered (forget registering the guns themselves; THAT is idiotic). Thus, legitimate firearm retailers have a criteria upon which they can sell their goods.
Bear in mind, none of these measures have a significant impact on criminal enterprise, especially gangs and organized crime. They do reduce the number of accidents, however, and they also reduce the number of "He just lost it" shootings - a major factor in those events is immediate psychological distress, in which case removing the means to commit an act often reduces the liklihood of it actually occurring.
I'm not an advocate of gun-control so much as gun owner control. US states need to start mandating a registration and licensing process for people who wish to possess any firearms - that is not to say this must be extremely difficult or demanding. The idea is to stem the number of "questionable" gun sales from legitimate retailers, and actually confine illegal gun sales and possession to an undeniably criminal element. This is essentially what Canada does, and I fully support it. I've been through the licensing process. I can legally possess and accquire any firearm which can be legally purchased or imported into this country. It wasn't hard.
I noticed that some favor the idea of concealed carry on campus. This is a sticky issue. Yes, a trained individual with a concealed carry permit could likely have stopped this guy. An untrained "hero" in a situation like this could get himself and more people killed (this particular incident is likely a bad example). I'm on the fence when it comes to concealed-carry, but I don't think just anyone should be able to apply for it. Some form of law enforcement or military training, or at least a course on emergency use, should be a mandatory requirement.
All this said, there is no clear solution. The US has a very specific culture which favors self-defense in lieu of law enforcement protection, and so it is difficult to make specific suggestions which do not contradict the culture at its core.