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 afcontinue="DCvsTC_Benchmark_Core_i7_940.png|1544" />
  </query-continue>
  <query>
    <allfileusages>
      <f fromid="147" ns="6" title="File:Bulbgraph.png" />
      <f fromid="61" ns="6" title="File:DC scr CD encr.png" />
      <f fromid="61" ns="6" title="File:DC scr about.png" />
      <f fromid="61" ns="6" title="File:DC scr bootconfig.png" />
      <f fromid="61" ns="6" title="File:DC scr encr.png" />
      <f fromid="61" ns="6" title="File:DC scr main.png" />
      <f fromid="61" ns="6" title="File:DC scr settings.gif" />
      <f fromid="1544" ns="6" title="File:DCvsTC Benchmark 2x Intel Xeon E5540.png" />
      <f fromid="1544" ns="6" title="File:DCvsTC Benchmark Core i5 660.png" />
      <f fromid="1544" ns="6" title="File:DCvsTC Benchmark Core i7 2600K.png" />
    </allfileusages>
  </query>
</api>