As a user, I want to work on a MapStory alongside other registered users, and then publish it as being by all of us who worked on it.
Currently a mapstory can only be published under a single account, and be worked on by the owner of that account. Multi-user storytelling will let the same mapstory be attributed to multiple account. Also, multi-user mapstorytelling would ultimnately let multiple users work on the same mapstory at the same time, much like they would a google doc.