You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <allimages gaicontinue="TEW-658BRM_INTERNET-SETUP_PPoE.png" />
  </query-continue>
  <query>
    <pages>
      <page pageid="340" ns="6" title="Fichier:TEW-658BRM ADVANCED IPv6-WAN IPv6-CONNECTION-TYPE.png" imagerepository="local">
        <imageinfo>
          <ii timestamp="2012-12-09T18:54:43Z" user="Cacheln" />
        </imageinfo>
      </page>
      <page pageid="341" ns="6" title="Fichier:TEW-658BRM ADVANCED IPv6-WAN PPPoE.png" imagerepository="local">
        <imageinfo>
          <ii timestamp="2012-12-09T18:55:57Z" user="Cacheln" />
        </imageinfo>
      </page>
      <page pageid="337" ns="6" title="Fichier:TEW-658BRM BUTTON-APPLY.png" imagerepository="local">
        <imageinfo>
          <ii timestamp="2012-12-09T18:37:23Z" user="Cacheln" />
        </imageinfo>
      </page>
      <page pageid="330" ns="6" title="Fichier:TEW-658BRM INTERNET-SETUP INTERNET-SETTINGS.png" imagerepository="local">
        <imageinfo>
          <ii timestamp="2012-11-05T15:08:28Z" user="Cacheln" />
        </imageinfo>
      </page>
    </pages>
  </query>
</api>