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>
    <images imcontinue="1|White_fd3s_rz.jpg" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1" ns="0" title="Main Page">
        <images>
          <im ns="6" title="File:13bexp.jpg" />
          <im ns="6" title="File:787b lemans.jpg" />
          <im ns="6" title="File:Cosmo sport profile.jpg" />
          <im ns="6" title="File:Former 0013s.jpg" />
          <im ns="6" title="File:Grey sa22c savanna turbo.jpg" />
          <im ns="6" title="File:MazdaRX77245909 1005.jpg" />
          <im ns="6" title="File:Mazdaspeed RX-8 concept.jpg" />
          <im ns="6" title="File:Mysinglevachose.jpg" />
          <im ns="6" title="File:Red savanna fc3s gtx.jpg" />
          <im ns="6" title="File:Renesis cutout.jpg" />
        </images>
      </page>
    </pages>
  </query>
</api>