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" encoding="utf-8"?>
<api>
  <query>
    <pages>
      <page pageid="1" ns="0" title="Main Page">
        <revisions>
          <rev user="Huston" timestamp="2012-03-12T17:14:58Z" />
          <rev user="Huston" timestamp="2012-03-12T17:10:50Z" comment="TIGRESS -&gt; Research Computing" />
          <rev user="Huston" timestamp="2011-09-15T19:49:15Z" comment="Added links to initial general documentation pages" />
          <rev user="Lkoven" timestamp="2007-06-19T15:41:25Z" comment="Made &quot;ask us&quot; a link to the Requesting assistance page" />
          <rev user="Huston" timestamp="2007-05-23T13:43:12Z" />
        </revisions>
      </page>
    </pages>
  </query>
  <query-continue>
    <revisions rvstartid="820" />
  </query-continue>
</api>