You are looking at the HTML representation of the XML format.
HTML is good for debugging, but probably is not suitable for your application.
See complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <allimages gaifrom="T&#039;Thuun&#039;s Marauders - Mayoi Pyramid.jpg" />
  </query-continue>
  <query>
    <pages>
      <page pageid="17631" ns="6" title="File:T&#039;Thuun&#039;s Marauders - Arwic Pyramid.jpg" imagerepository="local">
        <imageinfo>
          <ii timestamp="2008-10-29T15:52:46Z" user="An Adventurer" />
        </imageinfo>
      </page>
      <page pageid="17629" ns="6" title="File:T&#039;Thuun&#039;s Marauders - Ayan Pyramid.jpg" imagerepository="local">
        <imageinfo>
          <ii timestamp="2008-10-29T15:51:42Z" user="An Adventurer" />
        </imageinfo>
      </page>
      <page pageid="21176" ns="6" title="File:T&#039;Thuun&#039;s Marauders - Candeth Keep Device.jpg" imagerepository="local">
        <imageinfo>
          <ii timestamp="2008-11-13T04:30:05Z" user="Sanddh" />
        </imageinfo>
      </page>
      <page pageid="21175" ns="6" title="File:T&#039;Thuun&#039;s Marauders - Isle of Tears Device.jpg" imagerepository="local">
        <imageinfo>
          <ii timestamp="2008-11-13T04:29:38Z" user="Sanddh" />
        </imageinfo>
      </page>
    </pages>
  </query>
</api>