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>
    <allredirects garcontinue="Count_to_Six_and_Die_(The_Vacuum_of_Infinite_Space_Encompassing)" />
  </query-continue>
  <query>
    <pages>
      <page pageid="7558" ns="0" title="Barbara Warner" />
      <page pageid="9281" ns="0" title="Beatrice Warner" />
      <page pageid="1560" ns="0" title="Born Again" />
      <page pageid="6430" ns="0" title="Born Villain (album)" />
      <page pageid="8134" ns="0" title="Cameo appearances in music videos" />
      <page pageid="16233" ns="0" title="Campaign" />
      <page pageid="8193" ns="0" title="Cat in the Hat" />
      <page pageid="1444" ns="0" title="Celebritarian codes" />
      <page pageid="2910" ns="0" title="Charlie Clouser" />
      <page pageid="1562" ns="0" title="Coma Black" />
    </pages>
  </query>
</api>