You forgot to mention something I only discovered recently, but now use all the time: you can even ctrl-V (that's right, paste) an image from the clipboard onto Imgur. Super useful if you just made a quick sketch of something in GIMP, just ctrl-C, go to imgur.com, ctrl-V, click to upload, click to copy URL, done!

Only thing that would be easier if GIMP had a "save to Imgur" feature (and I bet there's a plugin for that ...).