gistfile1.rb

#commit models
class Commit < ActiveRecord::Base
  attr_accessible :commit_url, :author, :commit_message
  set_inheritance_column :provider
end
class GithubCommit < Commit
end 

#story model 
class Story < ActiveRecord::Base
  has_many :notes
  has_many :commits
  
  def activities
    notes.zip(commits)
  end
end

#view 
<% story.activities.each do |activity| %>
   <%= render :partial => "#{activity.class}" %>
<% end %>