The incident in the article, which is about the groups of youths shooting at cars at Yonge and Bloomington probalbly has nothing to do with airsoft guns, but with the crossman airguns. I am pretty sure about this because i know that area pretty well, and there is a Canadian Tire right there, where they can go and purchase these airguns.
And about banning replica guns, i think only airguns and Canadian guns should be banned. My reason to this is: those guns are probably what most parents are buying their kids, or what kids are buying the most. I am from hong kong and have known about airsoft guns throughout mylife. When i started to get into airsoft, which was around 6 years ago (when i was in Canada), none of my friends or their parents knew what an airsoft gun was. My point is not many parents or kids that are raised in Canada know what an airsoft gun is, all they know about are the guns they see when they go to Canadian tire, and since those are the closest to real guns they can get, they buy them and be idiots with them. Not like airsofting, where there are forums telling people what is wrong and what not to do; there aren't any forums for those airguns; so the people who buy them don't know about the responsibilites when owning one of those airguns.
So my proposal to this issue it to ban all Canadian tire (or walmart, etc) guns, and have a age limit on buying airsoft guns (what greylocks said), or even have to have a license to play with airsoft guns.