I am a military Helicopter pilot and I have literally come back with a UAV sticking out of the side of my aircraft after a mid-air with a small drone. There are lots of growing pains with these things, and they are no where ready for integration in the national airspace system. A growing conflict with military use of UAVs is that they are often being operated by non-pilots(cheaper to train). In many cases the smallest drones are operated by infantrymen who throw these things into the air and rely on big sky theory to separate them from the aircraft providing Close Air Support. Non-pilots typically have less diversity of experience and a lot less air-sense when it comes to situational awareness.
The most likely user of this technology is Law Enforcement. The last thing civil aviation needs is some jack-hole beat cop throwing these things into the air to look for a guy on a stolen bicycle and have a mid-air with an airliner on approach because he dose not understand what is going on above him, or have any responsibility for his actions because his personal safety is not directly tied to the operation of his aircraft. They cant be trusted to use tazers, why the heck would we give them UAVs?