title: Problems with Backbone.Model callback and THIS
body: <p>I'm building a simple weather widget. The current weather conditions are read out of the National Weather Service xml file and then I want to parse and store the relevant data in the model but the callback for the $.ajax won't connect (the way I'm doing it).</p>
  
  <pre><code>var Weather = Backbone.Model.extend({
          initialize: function(){
              _.bindAll( this, 'update', 'startLoop', 'stopLoop' );
              this.startLoop();
          },
          startLoop: function(){
              this.update();
              this.interval = window.setInterval( _.bind( this.update, this ), 1000 * 60 * 60 );
          },
          stopLoop: function(){
              this.interval = window.clearInterval( this.interval );
          },
          store: function( data ){
              this.set({
                  icon : $( data ).find( 'icon_url_name' ).text()
              });
          },
          update: function(){
              $.ajax({
                  type: 'GET', 
                  url: 'xml/KROC.xml', 
                  datatype: 'xml' 
              })
              .done( function( data ) {
                  var that = this;
                  that.store( $( data ).find( 'current_observation' )[ 0 ] );
              });
          }
      });
      var weather = new Weather(); 
  </code></pre>
  
  <p>The data is read correctly but I can't get the done function of the call back to call the store function. (I would be happy if the "done" would just parse and then do "this.set".</p>
  
  <p>Thanks in advance for your help.</p>