Its not going to happen anytime soon in the UK. Current civil aviation legislation, and any foreseeable developments of it will not permit a drone free for all.
When the media announces that there is a certified drone sense-and-avoid system on the market to stop drones bumping in to anything (on the ground and in the air) and an insurance company will take on the risk of airborne deliveries, its all a lot of hot air. Current news stories deserve to go straight into "trash".