It is safe to say that 99.999% of people would never issues death threats, but when you're dealing with about 200 million English-speaking internet users, all it takes is that 0.001% to cause all this ruckus.
People like TotalBiscuit have repeatedly stated that he receives many death threats. Everybody who's famous will receive them at some point. Shoot, even I have received them after I went on TotalBiscuit's show regarding paid Skyrim mods.
As many of you have stated, there really isn't a way to stop the sub-1% who are insane, sociopathic, and incapable of reason. I personally think this type of stuff is best ignored by the media because giving any form of terrorism more attention is playing into their hand.
Intellectual thought for the day: if all death threats were reported on, journalism sites wouldn't be able to fit them on the page every day. Is it good that sites seem to deem only certain death threats news-worthy?