This calls back to a Rails (or other) web service to get theme information, so that it is easy to keep the rails and WP sides in sync.
If you are using Passenger and Apache, put this in your conf file (assuming you want the WordPress site to be accessible
<Directory "/path/to/rails/app/public/news"> PassengerEnabled off AllowOverride all </Directory>
If you create a symbolic link in your public folder to the wp site, then you can use the URL /news to get to your blog:
cd path/to/rails/app/public ln -s /path/to/wordpress/installation news