The Federal Aviation Administration may want to go through some rigorous testing before it allows commercial drone flights on a broader basis, but the National Transportation Safety Board isn't willing to wait that long.
One of the Board's judges has determined that the FAA currently has no authority to regulate drones; the move effectively makes drones legal, and it spares a pilot from a $10,000 fine for shooting a commercial with his unmanned aircraft. The Administration has no rules on the books for such vehicles, according to the judge, and the 2007 policy notice it has been using to ban drones isn't binding.
There's still a possibility that the FAA will create enforceable rules down the line. For now, though, Amazon and UPS don't have to worry about legal threats to their delivery drone plans.