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="民視支持.jpg|2" />
  </query-continue>
  <query>
    <pages>
      <page pageid="2" ns="0" title="首頁" />
      <page pageid="71" ns="0" title="張大千" />
      <page pageid="75" ns="0" title="施世彭(施志剛)" />
      <page pageid="180" ns="10" title="模板:鄭鴻文 書法家 支持" />
      <page pageid="206" ns="0" title="02" />
      <page pageid="742" ns="0" title="2" />
    </pages>
  </query>
</api>