Drupal websites that allow users to create content provide a challenge for development. When a copy of the main site is used for development, users can create new content. Then, if the developers copy the devel website to live, the user-created content is overwritten.
There should exist automated ways of using drush to copy the structure and configuration of the development website to the live site, but not mess with the content. We have struggled with how to do this.
I believe that a session on this topic would be of great use to the drupal community.