Kapost plug-in by iamnader and icebreaker allows WordPress sites to have an adjoining “newsroom” associated with the blog. Each newsroom allows for your site’s community to submit posts for you to view, edit, and – of desired – promote to your WordPress site. Enabling your community to write for you provides more content and a more engaged audience.
The plug-in creates a sidebar widget that, if enabled, displays posts submitted from the community (sorted by recency, popularity, etc.). The widget also contains a “submit a post” button that on click displays a text editor in a pop-up that a site visitor can use to submit a post.
Current version 1.8 Requires WordPress Version: 2.9 or higher Compatible up to: 3.0.1
WordPress download: http://wordpress.org/extend/plugins/kapost-community-publishing/
More info: http://kapost.com/