respond_to do |format|
      format.html
      format.rss {
        render_rss_feed_for(@posts, { :feed => {:title => @rss_title, :link => recent_url},
          :item => {:title => :title, :link => Proc.new {|post| user_post_url(post.user, post)}, :description => :post, :pub_date => :published_at}