New here but I feel like I have a little insight, perhaps somewhat repetitive, to what has already been said.
UAVs will very soon, from the perspective of trends, experience a heavy push in applications that meet the 3 Ds - applications that are Dirty, Dangerous, and Dull. Having said that, we are already seeing heavy research in the agricultural, resource management, and mapping sectors with substantial interest in the use of unmanned systems. They are aimed at improving safety and limiting operator liability in areas that are not populated or, if at all, very very sparsely populated.
Unmanned systems will NEVER replace passenger ferrying operations. However, they will very soon start chipping away at the aforementioned sectors.