So far, I'm probably not as up to date as the rest of you, but I think I'll give some opinions based on what I know.
First: Gun control. We all know that this sort of thing keeps coming up. I think that if you're going to debate about it, be sure to reference actual numbers. This morning on NPR, I heard two handguns (one semi-automatic with extended clips and a .22 caliber) were involved. Could restricting/banning handguns have an overall benefit for society? Does handgun possession prevent enough crime to offset its convenience for criminals? Would restrictions on ammunition and large clips help? I don't know. I want to hear empirical discussion, not some extremist NRA member holding up a shotgun or whatever, saying "from my cold, dead hands!"
Second: Which part of society is to blame (if any)? This is the real sticky wicket, and before we even knew anything, we've had people spouting off about it being caused by evolution, atheism, violent videogames, not having "American" DNA, and so on. I can imagine Communism's going to get thrown in since the guy was Asian. Since he was considered a "misfit," I think we can expect the same nerdophobia that followed Columbine. Let's wait until we hear a bit more, then we can figure out his motives, okay?