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>
<allusers aufrom="塚本真也" />
</query-continue>
<query>
<allusers>
<u userid="17" name="下村芳樹" />
<u userid="33" name="久米保" />
<u userid="5" name="事務局" />
<u userid="6" name="伊藤高廣" />
<u userid="23" name="伊達宏昭" />
<u userid="16" name="佐野泰久" />
<u userid="30" name="吉岡勇人" />
<u userid="31" name="吉田典正" />
<u userid="13" name="垣内弘章" />
<u userid="37" name="堤正臣" />
</allusers>
</query>
</api>