First cut at Image Sharing.

I'm going blind from looking at it, it's a huge first pass that tries to incorporate a bunch of things from other sources, including:
http://www.rackspace.com/knowledge_center/article/cloud-images-frequently-asked-questions#image-sharing
http://docs.rackspace.com/images/api/v2/ci-devguide/content/image-sharing.html
http://docs.openstack.org/api/openstack-image-service/2.0/content/producer-consumer-communication.html
http://docs.rackspace.com/images/api/v2/ci-devguide/content/member-statuses.html

I feel confident you will point out some areas I may have excluded. :) Taking a quick break.