Not with a Bang but with a whisper : 2013

Children: ensuring the drone has safe guardes in place to make the landing procedure aware of children

Pets: for curious dogs that want to play, perhaps a dog whistle equivalent frequency could be employed.

Weather: some conditions will likely make drone air delivery temporarily unavailable, a system will need to be put in place to monitor weather on the flight pathes of the drones.

Drone recovery procedures: With thousands of drones flying hundreds of thousands of hours there will surely be failure mid-flight. The AI of the drone will need sub routines to limit damage from a drone experiencing flight failure. Also there will need to be a procedure in place to recover a drone that has failed to make delivery or failed to return from delivery. Perhaps a larger tow drone.

Bird avoidance: with thousands of drones making deliveries in a city the likelihood of encountering wildlife will be much greater than the hobyest level of drone usage today. Similar to the dog whistle a predatory bird call might be usefull to redirect birds.

Awareness of surroundings: as well as GPS and landing sensors the drone will need some manor of optical awareness to identify the above listed hazards.

Response to abuse/vandalism/theft: the technology present on smart phones that allow them to transmit their location and pictures of their surroundings should be sufficient. The difficulty will probably lie in automating the trigger to initiate the theft theft/or vandalism procedures.

Legal response for drone damage: precident will need to be established for legal recourse when an individual damages the drone, and when the drone damages an individuals property or person.

Amazon will need to build a system into the amazon prime air application process to allow customers to define the landing area for their package.

Appartments and high-density housing will pose unique delivery challenges. Perhaps the drones could become precise enough to deliver to a balcony.

Airspace availability will sometimes change. The servers that define the drone flight pathes will need dynamic definable airspace.

For civil disasters Amazon should be prepaired to have their drone fleet commandeered by civil authorities for disaster response. This could be a tremendous source of public trust and highly lucrative if Amazon is smart with how it leverages this resource politically.

I can't wait to see this system in action!

A few things already in the works: Tacos by quadcopter!
Previous article on food delivery by copters: Why has no one done this yet?
First article: Quad and Hexacopters.

Its all Legos.

Humanity has always looked at systems too complex for understanding with a mixture awe and wonder, similar to the audience of a magician concluding only that there are forces at work beyond what we understand. Every field that is now science has it's roots in a magic wonder. The stars were once the resting place of gods, our bodies were held together by good and evil forces depending of the culture you ask. Where our understanding ended we created myth and magic to fill the dark void of understanding.

The Human body is getting closer and closer to undergoing a similar transition. In the same way that there isn't any mystery to how the earth swings around the sun the human body and the systems it holds are the focus of Galileo's telescope the human body has been revered by almost every religion as divinely inspired or created. As our modern understand of our physical bodies grow religion may have the same impact on our future progress as it did during Galileo's time.

Several biotech developments are maturing which our ability to recreate human systems. The intersection of 3D printing and stem cell creations will lead to the ability to rapidly synthesize new parts for broken bodies. Every researcher when asked how long will it be until they can save someone with this technology always replies with the obligatory answer, putting the solution far enough into the future as to not be considered soon. What is always missed in the follow up questions is how will lateral technological developments impact the ability of this technology. And just like Legos a single piece is very limited but stack a few together and something entirely new develops out of the parts. No gigantic step forward will bring the human race to any break-through its always a series of small steps that will finally arrive at the easy rebuilding of damaged bodies.