title: Windows Phone 8 Map control - how to get map bounds
body: <p>I'm using the brand new Windows Phone 8 Map control, but have run into an issue:  I need to get the LocationRectangle of the map's bounds, in other words the Latitude span and Longitude span.</p>
  
  <p>With the Bing Maps control, you can just do:</p>
  
  <pre><code> LocationRect bounds = map.Bounds;
  </code></pre>
  
  <p>...however, there seems to be no relevant fields in this new control.  Can anyone help, or do I need to reverse engineer the various Zoom Levels and work it out based on the center point, Zoom Level and pixel height/width ?</p>