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="CDCchart.gif|181" />
  </query-continue>
  <query>
    <pages>
      <page pageid="93" ns="0" title="Bureau of Labor Statistics" />
      <page pageid="127" ns="0" title="British Atmospheric Data Centre" />
      <page pageid="181" ns="0" title="CDC FluView" />
      <page pageid="188" ns="0" title="Broad Institute Cancer Datasets" />
      <page pageid="256" ns="0" title="BioResources" />
      <page pageid="269" ns="0" title="BioMed Central" />
      <page pageid="308" ns="0" title="BioPerl" />
      <page pageid="329" ns="0" title="Bellerophon server" />
      <page pageid="445" ns="0" title="BBC API" />
    </pages>
  </query>
</api>