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="Burrow_Detection" />
  </query-continue>
  <query>
    <allpages>
      <p pageid="93" ns="0" title="Badlands Buildings" />
      <p pageid="5" ns="0" title="Balanced Melee Mapmaking" />
      <p pageid="79" ns="0" title="Bin Dialog File Format" />
      <p pageid="78" ns="0" title="Bin Dialog Reference" />
      <p pageid="65" ns="0" title="Binary Countoffs" />
      <p pageid="97" ns="0" title="Bridge Terrain" />
      <p pageid="66" ns="0" title="Bring" />
      <p pageid="6" ns="0" title="Bring Condition Bug" />
      <p pageid="154" ns="0" title="Brush Files" />
      <p pageid="85" ns="0" title="Bunker Disabling and Stacking" />
    </allpages>
  </query>
</api>