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>
    <random>
      <page id="4673" ns="0" title="Transmission Interchange Information" />
      <page id="4712" ns="0" title="1980 California Manual With and Without Air Conditioning Four Cylinder" />
    </random>
  </query>
</api>