Heroku PaaS itself is proprietary. Their dashboard, monitoring and other tools are proprietary.
PaaS services based on open source PaaS solutions (Deis + Docker, Flynn + Docker) and proprietary PaaS solutions ( Tutum + Docker, for example) will look after my infrastructure. Or I will host it myself. In any case I'll be able to migrate my containers to any other infrastructure easily, quickly and with nearly zero additional configuration.
PaaS services based on open source PaaS solutions (Deis + Docker, Flynn + Docker) and proprietary PaaS solutions ( Tutum + Docker, for example) will look after my infrastructure. Or I will host it myself. In any case I'll be able to migrate my containers to any other infrastructure easily, quickly and with nearly zero additional configuration.