You know, IIRC the first Rails demo actually used building a blog app as example. 8 years later and still no one has come up with a real Wordpress/Drupal/Mediawiki alternative - or at least none that's gained any significant userbase. I often wonder why..
The problem is that Wordpress is vehemently anti-MVC, and its plugin structure depends on this. You'd have to design an entirely different system to work on Rails.
