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>
    <allfileusages gafcontinue="Pannekaken.spx|115" />
  </query-continue>
  <query>
    <pages>
      <page pageid="10" ns="0" title="Bamse Brakar" />
      <page pageid="15" ns="0" title="De tre bukkene Bruse som skulle gå til seters og gjøre seg fete" />
      <page pageid="71" ns="0" title="Hanen, gauken og århanen" />
      <page pageid="72" ns="0" title="Hanen og høna" />
      <page pageid="76" ns="0" title="Haren som hadde vært gift" />
      <page pageid="81" ns="0" title="Hver synes best om sine barn" />
      <page pageid="97" ns="0" title="Kjæresten i skogen" />
      <page pageid="156" ns="0" title="Elementært" />
      <page pageid="166" ns="2" title="Bruker:Haakon" />
    </pages>
  </query>
</api>