Given the unmet need to allow users only access to edit specific pieces of content, I created a simple plugin called Editorial Access Manager.
By default in WordPress, we can create users and assign them to roles. Roles are automatically assigned certain capabilities. However, sometimes default roles are not enough, and we have one-off situations. Editorial Access Manager lets you set which users or roles have access to specific posts (as well as pages and custom post types).
Only the Administrator and Editor role have access to manage pages by default in WordPress. Making a user an Editor gives them a lot of power. I ran into the situation where we wanted a Contributor (less power than an Editor) to be able to edit only a few pages hence the need for this plugin.
My plan is to eventually integrate this plugin with EditFlow allowing people to assign User Groups to have access to specific pieces of content.
Any development help on this project would be much appreciated! Fork the Github repo.