It's actually more scary than amazing. Military has been working on swarm ai and can be used in really bad ways.
Each drone knows its proximity to the others and programming them isnt all that different than program which pixel on a screen do what from frame to frame.
I saw a show about swarms of drones that were dropped from a cargo plane..
They were initially scattered (as you can imagine) but quickly came back together and formed a single unit. They only last a few minutes (right now), but imagine in 10 years what a swarm of intelligent drones can do!!!