Imgur is shooting itself in the foot à la Tumblr, stop using it ASAP

In short, the old fan favorite image host Imgur is banning porn and will wipe all previous porn along with a lot of other things. So all the porn will be gone, and anything you linked will be dead.

Long version: Imgur is updating their TOS to no longer allow porn as well as scrubbing old uploads and unregistered user uploads. They're like lemmings following Tumblr's lead, because they're convinced a 1bil dollar company that later sold for literally less than pennies on the dollar was the perfect example to follow. Best to avoid using it or you'll have a lot of dead links floating around soon (I most certainly will)

Some alternatives are things like postimg, imagebam, pimpandhost, etc