Amazon has been developing a program they call ‘Seller Flex’ which allows them to do deliveries for third party suppliers (this is Amazon delivering packages for products they do not stock, but offer through their website). This will largely be competition for FedEx and UPS who currently do most of these types of deliveries.
The implications for warehousing is that individual sites around the city that stock different goods will now be more integrated into a network of warehouses. This means space needs could be reduced, efficiencies could improve and there will start to be added benefits of having various key warehouses located near each other so that Amazon can more easily access and service them all. Amazon will be streamlining delivery while not having to own all of the individual warehouses or merchandise themselves.