Fedex and UPS suffer from the innovator's dilemma which will make it hard for them to build the best drone service with the right business model because it means they'll lose money, sunk investments and jobs relative to their old business model.

Anyway, this is probably a field rich with patents and amazon with their acquisition of kiva robotics and their attraction as an employer in this field with this PR, will grab quite a few patents and make it quite hard for other companies to compete.