On: When Drones Fall From The Sky

The difference between unmanned airplanes and quadcopters is especially important, IMO.

Only to the extent that there is a scale issue. If it can fall from the sky and only give someone it lands on a bruise then it isn't much of a safety issue. A big quadrocoptor could do some damage.

Even a big quadrotor is a few orders of magnitude smaller than an unmanned aircraft.

I think that when regulation becomes more mature, weight class and speed will be central issues.

If the only difference is the scale of risk, then you should include many other things, like paper airplanes, kites, and baseballs.