I just looked up Imgur on Wikipedia because of your comment, and found out that it's supposed to be pronounced "imager"!

Not only did I not know this all this while, I've also been referring to it as "im-goor" in all my conversations. Partly because I really really couldn't care less, and partly because said conversations have flowed just well even with my so-called mispronunciation, I'm just going to continue calling it "im-goor".