I don't think gamma bursts are the worst of our worries. The closest thing to us is... well... really fucking far. Our solar system is somewhat desolate. Asteroids are a much more likely catastrophe, and for all intents and purposes, can be just as devastating. Go ask the dinosaurs. Black holes aren't fun either.
Asteroids, nuclear holocaust, biowarfare, and now gamma busts.........how long until someone sells gamma-shields on ebay? Seriously, all this paranoia yet since hiroshima and nagasaki nobody died from atomic bombing. Theres a higher chance of falling in a pool with a toaster in hand than being killed by an asteroid or a meteor. And since 9/11 that we dont see anyone with anthrax, or bird flu for that matter... On the other hand, you know which are the real WMDs? knifes and regular guns. Combined they have killed hundreds of millions, if not billions, through human history. Right now theres a genocide in sudan, just like there was one in rwanda 10 years ago, and both were carried with bullets and machetes. Both the jewish and armenian holocaust were made possible with the use of guns and common industrial machinery. No nukes, pretty much no bombing at all, and dont even mention bioweapons (althought they used gas on the jews, but that was WWI tech, nothing fancy). But my point is: fuck catastrophes. As far as I know I'm already living in a flying blue madhouse full of psychopath monkeys with guns and blades. What the fuck do I care about gamma bursts? Kinda, but humanity lost his phone number eons ago, so when the shit hits the fan theres no way we can reach him... And Jupiter, didnt you see that bigass black thing?;-)