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>
    <alllinks galcontinue="Binary_Package_Server|285" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1" ns="0" title="Main Page" />
      <page pageid="27" ns="0" title="OpenLDAP Services: Backup" />
      <page pageid="36" ns="2" title="User:Pat" />
      <page pageid="51" ns="0" title="2013-08-13 Telephone Conference DEVROOM / stepping stone GmbH" />
      <page pageid="52" ns="0" title="2013-08-14 stepping stone GmbH Development Meeting" />
      <page pageid="54" ns="0" title="2013-08-16 stepping stone GmbH Development Meeting" />
      <page pageid="55" ns="0" title="2013-08-19 stepping stone GmbH Development Meeting" />
      <page pageid="221" ns="0" title="Gentoo Infrastructure" />
    </pages>
  </query>
</api>