The FAA has approved the first commercial drone flights over land in the US, and they will be for critical infrastructure protection: specifically to monitor the oilfields, roads, pipelines, and oil production equipment on Alaska's North Slope. The lucky drone is the AeroVironment Puma AE, a shoulder-launched, 1.4 meter (4.5 ft) long beauty with a military pedigree. Its lucky operator is BP. The increased and more efficiently acquired situational awareness that the Puma AE will give BP in managing its infrastructure is easy to see.
In coming years, drones will be especially useful for monitoring critical infrastructure that relies on facilities in remote areas (energy, telecoms, defense, and emergency services like search and rescue), or that uses vast tracts of land and water (water supply, agriculture, railways, etc.)
Neither the FAA nor AeroVironment has mentioned anything about securing the UAV against cyber attack (or physical attacks for that matter). I don't know how much the FAA looks into cyber security threats and vulnerabilities when granting approval for an aircraft to operate, but I suspect not a whole lot. The day will come when someone shoots down a commercial drone, or hacks into its control systems and and crashes it into something or someone. Or steals it. We know that Iran at least claimed to do that when it captured a US drone in 2011.