rubyusers.rb

%w(open-uri hpricot).each { |lib| require lib }
BASEURL = "http://www.rubyusers.com"
puts Hpricot(open("#{BASEURL}/users/list")).search("//li[@class^='size_']/a").map { |a|
  [a.inner_text, Hpricot(open("#{BASEURL}#{a[:href]}")).search("//p/li").size]
}.sort_by{|e|e[1]}.reverse.map{|e|e*': '}