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="Day_2_-_Dad_impersonating_an_alien.JPG|1349" />
  </query-continue>
  <query>
    <allfileusages>
      <f fromid="1300" ns="6" title="File:CPU-bang-for-buck.png" />
      <f fromid="1349" ns="6" title="File:Day 1 - Alpen.JPG" />
      <f fromid="1349" ns="6" title="File:Day 1 - Kogen.JPG" />
      <f fromid="1349" ns="6" title="File:Day 1 - Most useless kettle ever invented.JPG" />
      <f fromid="1349" ns="6" title="File:Day 1 - Snoopy themed rubbish bin.JPG" />
      <f fromid="1349" ns="6" title="File:Day 1 - The snoopy themed bed covers.JPG" />
      <f fromid="1349" ns="6" title="File:Day 1 - The snoopy themed room.JPG" />
      <f fromid="1349" ns="6" title="File:Day 1 - The snoopy themed tissue box.jpg" />
      <f fromid="1349" ns="6" title="File:Day 1 - meeting area.JPG" />
      <f fromid="1349" ns="6" title="File:Day 2 - Alpen.JPG" />
    </allfileusages>
  </query>
</api>