Images uploaded to imgur are showing broken image icons with a link containing the image description (which is usually just the generic "enter image description here"). When I click on the link I get a "Bad gateway" error at imgur.com. Is there a problem at Imgur?
Maybe the problem is resolving itself? As I was writing this question I uploaded the image below, and it first showed as a broken image, but it recovered while I was writing. But if I go to other questions I still see broken images, e.g. Custom Filters release announcement.