title: Google Maps Api V3: Overlay ImageMap with loading indicators
body: <p>I have an ImageMap overlay like the following:</p>
  
  <pre><code>var options = {
      getTileUrl: function(coord, zoom) {
          return myUrl+"?x=" + coord.x + "&amp;y=" + coord.y + "&amp;z=" + zoom;
      },
      tileSize: new google.maps.Size(256, 256),
      isPng: true
  };
  
  var overlay = new google.maps.ImageMapType(options);
  var map = new google.maps.Map(document.getElementById("map_canvas"), mapOptions);
  map.overlayMapTypes.insertAt(0, overlay);
  </code></pre>
  
  <p>Because the images can take a while to load, i want to show load indicators for the map (those common animated gifs for AJAX calls). I am not sure if the usability would be better if there is only one indicator for the whole map, or one indicator for each overlay tile. So, solutions and thoughts for both are welcome.</p>