First off, if package handling is more efficient using quad copters than wheeled robots, why doesn't Amazon use them inside their warehouse? It is a controlled environment (no weather, no wind, can have localizing beacons all over, fixed map, etc etc) and doesn't require FAA approval. Not to mention products in the warehouse are lighter weight and smaller because they haven't been packed for shipping yet.

I would argue that is at least a first step on this road if they ever intend to actually deliver packages by drones. The fact that they haven't done even that simple step before announcing it publicly makes me believe it was pure PR.