<p>This is a side effect of  <a href="http://meta.stackexchange.com/questions/95732/images-manually-uploaded-to-imgur-are-not-displaying/95734#95734">this</a>:</p>

<blockquote>
  <p>For all posts made on or after <a href="http://blog.stackoverflow.com/2010/08/new-image-upload-support/">August 17 2010</a>, any image urls in
  the form of <code>i.imgur.com</code> were changed to <code>i.stack.imgur.com</code>
  network-wide.</p>
  
  <p>This means, if &hellip;</p>
  
  <ul>
  <li><p>your post was made on or after <strong>August 17 2010</strong></p></li>
  <li><p><strong>you <em>MANUALLY</em> uploaded something to imgur, that is, outside of
  clicking the 'add image' button in our editor</strong></p></li>
  <li><p>your image URL will be broken and you'll have to manually edit it
  back to the old <code>i.imgur.com</code> form</p></li>
  </ul>
  
  <p>(please note this also implies <em>your image will disappear after 6
  months</em>, unless you <a href="http://imgur.com/register/upgrade">happen to own an imgur pro account</a> for your
  own personal use..)</p>
  
  <p>Sorry, we assumed that 99% of users would be using the default image
  upload support provided by the editor, so those users who deviated
  will be affected.</p>
</blockquote>

<p>It would appear that John T uploaded to imgur, but did not use the Image Uploader, hence the image was not stored under Stack Exchange's imgur account. </p>

<p>The bad news is that the <em>original</em> image has also been deleted, leading to a image link rot.</p>

<p><sub><sub>which reminds me, I need to scour my previous posts and transfer them to Stack Exchange imgur account </sub></sub></p>