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>
    <alltransclusions gatcontinue="Back|141" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1" ns="0" title="Main Page" />
      <page pageid="2" ns="0" title="IRidium Script API" />
      <page pageid="50" ns="0" title="List API" />
      <page pageid="53" ns="0" title="Drivers API" />
      <page pageid="54" ns="0" title="Tokens API" />
      <page pageid="55" ns="0" title="Systems API" />
      <page pageid="60" ns="0" title="IRidium GUI Editor" />
      <page pageid="64" ns="0" title="IRidium Util" />
      <page pageid="105" ns="0" title="Description of iRidium for Crestron" />
      <page pageid="124" ns="0" title="Concepts of Work with iRidium for Crestron" />
    </pages>
  </query>
</api>