Given the number of UAVs in the air and the altitudes they can operate at kind of reminds me of the late 40's and 50's in the US where a number of mid-airs occurred between military and civilian ac due to lack of coordination between the military and CAA. I hate to think of how many military, intelligence, homeland security, local police, state police units may be operating what at this point but I suspect coordination with commercial aviation authorities is not necessarily well established.