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>
    <pages>
      <page ns="0" title="API" missing="" />
      <page pageid="357" ns="0" title="Main Page">
        <revisions>
          <rev user="Wong" timestamp="2012-08-25T19:25:53Z" comment="moved [[Main Page]] to [[Facebook Developer Wiki]]: better SEO" xml:space="preserve">#REDIRECT [[Facebook Developer Wiki]]</rev>
        </revisions>
      </page>
    </pages>
  </query>
</api>