With regards to the explanation of this being an exaust cooler so hard to develop. Sorry, Nvidia's solution is a marvel of enginnering. looks impressive, performs impressively, no excuse.
AMD is in a tough financial situation so they simply didn't want to invest money in the development of the cooler. And in the end the current R9 290X with default cooling solution is not a product for normal user who wants to maintain their ears.
FYI, I just orderd the R9 290x. Reason is like most of us here, we are not normal PC users, and modding the cards cooler is not difficult for us, and that is where the card shines.