Admin Forum:Difference between wikia and nocookie.net url

I was just working to keep my site's page load latency low and found these URLs redirecteing to the same location. Is there any difference between them? If so, which one is the best to use in CSS?
 * http://images.wikia.com/seiyuu/ko/images/4/44/Sidebar-top-bottom.png
 * http://images4.wikia.nocookie.net/seiyuu/ko/images/4/44/Sidebar-top-bottom.png
 * http://images4.wikia.nocookie.net/__cb20120827043023/seiyuu/ko/images/4/44/Sidebar-top-bottom.png