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="Unfertig|45" />
  </query-continue>
  <query>
    <pages>
      <page pageid="3" ns="0" title="Bud Spencer und Terence Hill" />
      <page pageid="6" ns="0" title="Coders at Work" />
      <page pageid="8" ns="0" title="Die etwas anderen Cops" />
      <page pageid="21" ns="0" title="Knappe Wahlen" />
      <page pageid="23" ns="0" title="Mathematik" />
      <page pageid="24" ns="0" title="My Programming Language" />
      <page pageid="27" ns="0" title="Pirates of the Caribbean - Fremde Gezeiten" />
      <page pageid="36" ns="0" title="Save the Green Planet!" />
      <page pageid="41" ns="0" title="Stichtag" />
    </pages>
  </query>
</api>