Чем различают роли участников блога?

Из кодекса

Summary of Roles

* Administrator - Somebody who has access to all the administration features
    * Editor - Somebody who can publish posts, manage posts as well as manage other people's posts, etc.
    * Author - Somebody who can publish and manage their own posts
    * Contributor - Somebody who can write and manage their posts but not publish posts
    * Subscriber - Somebody who can read comments/comment/receive news letters, etc.