The pages pull off of a variable within the url, which means all pages have a ?p=Article in the URL string. That doesn't mean we can't get back the the Clean /Article URLs that everyone had when there were separate pages for each file though.
Through the clever use of an .htaccess file to add a custom 404 page, and some php to snag the last bit of the page, this means that you can now use either method to access your pages. It's entirely up to you. It even changes the navigation based on which site you want your clients to see.