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="Creativecommons.png" />
  </query-continue>
  <query>
    <pages>
      <page pageid="512" ns="6" title="File:12345.JPG" />
      <page pageid="727" ns="6" title="File:Auto Insurance 3025.jpg" />
      <page pageid="729" ns="6" title="File:Auto Insurance 3136.jpg" />
      <page pageid="737" ns="6" title="File:Auto Insurance 5296.jpg" />
      <page pageid="67" ns="6" title="File:Cclogo.png" />
      <page pageid="496" ns="6" title="File:Ccmonitorlogo.135.png" />
      <page pageid="176" ns="6" title="File:Cctest.png" />
      <page pageid="684" ns="6" title="File:Certification 3397.jpg" />
      <page pageid="693" ns="6" title="File:Certification 5581.jpg" />
      <page pageid="691" ns="6" title="File:Certification 984.jpg" />
    </pages>
  </query>
</api>