Docker Store Vs Docker Hub
The main difference is the commercial aspect (as in "revenue stream for Docker"), as pointed out in this Techcrunch article from Frederic Lardinois (@fredericl):
The idea behind the store is to create a self-service portal for Docker’s ecosystem partners to publish and distribute their software through Docker images — and for users to make it easier to deploy these applications.
While Docker already offered its own registry for containers (DockerHub: https://hub.docker.com/explore/), too, the Docker Store is specifically geared toward the needs of enterprises.
The store will offer enterprises “with compliant, commercially supported software from trusted and verified publishers, that is packaged as Docker images,” the company says, and feature both free and paid software.
Unsurprisingly, Docker will take a cut when a user installs a paid application through the store (though what exactly this revenue share agreement for paid-via-Docker content looks like is currently unclear).
The other difference is you don't get to see the Docker file that was used to create it. Yes you can reverse engineer it but its not perfect. https://github.com/CenturyLinkLabs/dockerfile-from-image
Personally I prefer to know what images contain, even if they are "certified" but then the whole payment model fails as soon as you can see the Dockerfile.
As far as I read these are the main purposes behind docker store :
Our goals with Docker Store are designed around bringing Docker users and ecosystem partners together.
Provide a scalable self-service system for ISVs to publish and distribute trusted and enterprise-ready content
Provide a publishing process that validates software quality, including; security scanning, component inventory, the open-source license usage and use of best practices in image construction.
Provide enterprise users with compliant, commercially supported software from trusted and verified publishers, that is packaged as Docker images.
We’ve added powerful search and browsing capabilities, including categorization.
So, I presume it's going to focus on commercial aspects of the app distribution and focus on consumers of the apps (something like Bitnami), but Docker hub would be for development community.
Reference :