title: Why isn't my computed property firing when the listener is changed?
body: <p>I have a simple ArrayController with a filteredContent computed property that lets me slice n' dice the array of ember objects. I have an interval property that when changed, I'd like to re-calculate the computed property.</p>
  
  <p>Yet with the below, my filteredContent property doesn't seem to fire when I "set" the interval</p>
  
  <pre><code>App.FilterController = Ember.ArrayController.extend({
      interval: 15,
      filterAvailable: function(event) {
          var selected = event.target.selectedIndex;
          var value = this.get('content')[selected].get('id');
          this.set('interval', value);
      },
      filteredContent: function() {
          var cleaned = this.get('content').toArray().filter(function(apt) {
              return apt.get('id') === null;
          });
          var sorted = cleaned.sort(function(a, b) {
              return Ember.compare(new Date(get(a, 'start')), new Date(get(b, 'start')));
          });
          return sorted;
      }.property("interval", "content.@each")
  });
  </code></pre>
  
  <p>In my template I have a select with a simple changeBinding that kicks off the "filter available" method</p>
  
  <pre><code>  {{view Ember.Select
    changeBinding="controller.filterAvailable"}}
  </code></pre>