You are looking at the HTML representation of the XML format.
HTML is good for debugging, but probably is not suitable for your application.
See complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query>
    <blocks>
      <block id="466" user="Superjack" by="Adilger" timestamp="2013-07-18T19:38:22Z" expiry="infinity" reason="Removing content from pages" nocreate="" autoblock="" noemail="" />
      <block id="465" user="Zeng1379" by="Adilger" timestamp="2013-07-18T19:37:18Z" expiry="infinity" reason="Spamming links to external sites" nocreate="" autoblock="" noemail="" />
      <block id="464" user="Yihang" by="Adilger" timestamp="2013-07-18T19:35:54Z" expiry="infinity" reason="Spamming links to external sites" nocreate="" autoblock="" noemail="" />
      <block id="463" user="YolandaKn" by="Adilger" timestamp="2013-07-18T19:29:06Z" expiry="infinity" reason="Spamming links to external sites" nocreate="" autoblock="" noemail="" />
      <block id="461" user="WinfredSe" by="Adilger" timestamp="2013-07-18T19:28:57Z" expiry="infinity" reason="Spamming links to external sites" nocreate="" autoblock="" noemail="" />
      <block id="460" user="WeldonSou" by="Adilger" timestamp="2013-07-18T19:28:47Z" expiry="infinity" reason="Spamming links to external sites" nocreate="" autoblock="" noemail="" />
      <block id="458" user="ValeriaBe" by="Adilger" timestamp="2013-07-18T19:28:34Z" expiry="infinity" reason="Spamming links to external sites" nocreate="" autoblock="" noemail="" />
      <block id="456" user="ThorstenR" by="Adilger" timestamp="2013-07-18T19:28:19Z" expiry="infinity" reason="Spamming links to external sites" nocreate="" autoblock="" noemail="" />
      <block id="454" user="StormyCAK" by="Adilger" timestamp="2013-07-18T19:28:07Z" expiry="infinity" reason="Spamming links to external sites" nocreate="" autoblock="" noemail="" />
      <block id="453" user="SoonYvz" by="Adilger" timestamp="2013-07-18T19:27:55Z" expiry="infinity" reason="Spamming links to external sites" nocreate="" autoblock="" noemail="" />
    </blocks>
  </query>
  <query-continue>
    <blocks bkstart="2013-07-18T19:27:43Z" />
  </query-continue>
</api>