With all this talk about Amazon and other less serious drone delivery concepts out there, there has been a large amount of discussion regarding the feasibility of delivering a package via drone for same day delivery or general delivery. While I don't think this is really all that feasible from a logistical or safety point of view, the idea is interesting.
What would be more realistic in my mind is a better system where you have autonomous ground vehicles carrying packages and UAV's. The autonomous ground vehicles being developed by various companies like Google's self driving cars are getting better and closer to integration into society, although I'm sure the regulatory hurdles will be just as painful.
The basic concept is you have that autonomous ground vehicle, probably just like a UPS truck outfitted with sensors, carry packages around the city to delivery locations much like is currently done using people. Simple enough but that alone wouldn't get the package to your door as I know I wouldn't want a van driving through my lawn up to my door to "fling" a package at my house or door. Instead, the autonomous UPS/FedEx/whatever truck dispatches a mutlirotor of appropriate size with your package to go from truck to door. Ground navigation is hard enough on the road but getting around a cluttered yard or sidewalk is going to be really hard. With a quad/hex/octo, you could easily have it take off, fly over all the obstacles, drop the package off near the door, and head back to the truck to essentially charge itself back up.
A delivery truck is going to be large enough to carry all the sensors it needs for autonomous navigation as well as packages and delivery "drones". As seen just a couple of days ago, Tridge and the team have also demonstrated a milestone in getting ArduPlane running and flying an airplane using Linux and ArduCopter likely is close behind. With that comes all sorts of possibilities like running SLAM or other computer vision algorithms, which would aid in a multi dropping a package off at your door.
If you want to get around the FAA regulations too, tether each multi to the truck! Then it's considered a tethered object and no different than a kite! You'll need a way to keep the tether from getting to the blades but there are enough people out there like Jack Crossfire that could whip something like that up and take care of that issue. It's one way to get things rolling without waiting for the FAA to get their act together.
With Amazon's announcement of drone delivery, much of the speculation has focused and assumed a drone is going to go from a warehouse to your door, which rightfully so, with just one or two images and a video of an octo, that's what people are going to think. However practicality suggests that's really unrealistic. It's going to take something more than just some quads to implement a system like this but I get the feeling it's going to be a combination of autonomous UGV's with UAV's that will get the job done.