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>
    <allpages apcontinue="NLCD" />
  </query-continue>
  <query>
    <allpages>
      <p pageid="233" ns="0" title="Basic Link Design Steps" />
      <p pageid="232" ns="0" title="Fade Mechanisms" />
      <p pageid="216" ns="0" title="FetchSRTM" />
      <p pageid="94" ns="0" title="Geobase" />
      <p pageid="4" ns="0" title="Global Land Cover Characteristics Data Base (GLCC World)" />
      <p pageid="102" ns="0" title="Import sites from text file" />
      <p pageid="195" ns="0" title="MRLC" />
      <p pageid="1" ns="0" title="Main Page" />
      <p pageid="104" ns="0" title="NASA" />
      <p pageid="205" ns="0" title="NED data in GridFloat format" />
    </allpages>
  </query>
</api>