Front-end:
    - Implement 'market-place' features such as comments/ratings for
      existing appliances.
    - Allow users to publish details/location of new appliances.
    - Provide access to reference images

Back-end:
    - Appliance repository becomes metadata catalogue/registry of
      appliances
    - Storage of images responsibility of appliance creator/owners
    - Provides storage for use by project
    - Do not support conversion of appliances on repository
    - Adopt standard for metadata schema (OVF?)

Integration with OpenNebula repository:
    - Caching of images at local site
    - Image must be available and registered with local site before use
    - Mechanism for integrating with local cache to be decided
    - Policy for deploying image at site
    - No synchronisation of images. Modifications result in new image.