title: CSS 3 filter (blur) not using transition duration
body: <p>I found this neat technique for cross-browser blurring. But it didn't look like the transition was having an effect, so I forked it and set the transition time and blur amount way up, and sure enough it's happening instantly.</p>
  
  <pre><code>img.blur {
  -webkit-filter: blur(30px); -moz-filter: blur(30px);
  -o-filter: blur(30px); -ms-filter: blur(30px); 
  filter: url(#blur); filter: blur(30px);  filter:progid:DXImageTransform.Microsoft.Blur(PixelRadius='3');
  -webkit-transition: 2s -webkit-filter linear;
  -moz-transition: 2s -moz-filter linear;
  -o-transition: 2s -o-filter linear;
  transition: 2s filter linear;
  }
  </code></pre>
  
  <p><a href="http://codepen.io/CSobol/pen/LGCiw" rel="noreferrer">http://codepen.io/CSobol/pen/LGCiw</a></p>
  
  <p>Does <code>transition: filter</code> not work with blur for some reason?</p>