If you want to move from Typo to Wordpress, you can use this to export the strange Wordpress RSS file format (comments and all).

Just add this to the XmlController :

  def wp
    @articles = Article.find( :all, :include => [:categories, :tags, :user, :blog])
  end

And then add this file (app/views/xml/wp.rxml):

// insert code here..
xml.instruct! :xml, :version=>"1.0", :encoding=>"UTF-8"

xml.rss 'version' => "2.0", 'xmlns:content' => "http://purl.org/rss/1.0/modules/content/", 'xmlns:wfw' => "http://wellformedweb.org/CommentAPI/", 'xmlns:dc' => "http://purl.org/dc/elements/1.1/", 'xmlns:wp' => "http://wordpress.org/export/1.0/" do
  xml.channel do
    xml.title @feed_title
    xml.link @link
    xml.language "en-us"
    xml.ttl "40"
    xml.description this_blog.blog_subtitle

    @articles.each do |a|
        xml.item do
          xml.title post_title(a)
          xml.content(:encoded) { |x| x << '<![CDATA[' + a.full_html + ']]>' }
          xml.pubDate a.published_at.rfc2822
          xml.guid "urn:uuid:#{a.guid}", "isPermaLink" => "false"
          author = a.user.name rescue a.author
          xml.author author
          xml.dc :creator, author
          for category in a.categories
            xml.category category.name
          end
          for tag in a.tags
            xml.category tag.display_name
          end
          xml.wp :post_id, a.id
          xml.wp :post_date, a.published_at.strftime("%Y-%m-%d %H:%M:%S")
          xml.wp :comment_status, 'closed'
          xml.wp :ping_status, 'closed'
          xml.wp :post_name, a.permalink
          xml.wp :status, 'publish'
          xml.wp :post_parent, '0'
          xml.wp :post_type, 'post'
          for comment in a.comments
            xml.wp(:comment) do
              xml.wp :comment_id, comment.id
              xml.wp :comment_author, comment.author
              xml.wp :comment_author_email, comment.email
              xml.wp :comment_author_url, comment.url
              xml.wp :comment_author_IP, comment.ip
              xml.wp :comment_author_date, comment.published_at.strftime("%Y-%m-%d %H:%M:%S")
              xml.wp(:comment_content) { |x| x << comment.full_html }
              xml.wp :comment_approved, '1'
              xml.wp :comment_parent, '0'
            end
          end
        end
    end
end

Then hit your typo blog at http://myblog/xml/wp and save the file to import through the WordPress interface.