small improvements

render :partial => filename, :object => @object can be written shorter since rails 2.0 like
render :partial => @object or render :partial => @collection
Also form_for is smart bout put and post for update and creation.

it helps watching older railcasts episodes :-)

app/views/notes/show.html.erb

@@ -1,3 +1,3 @@
 <div id="display_box_projects">
-  <%= render :partial => 'note', :object => @note %>
+  <%= render :partial => @note %>
 </div>