I believe that Web APIs will start a similar usability revolution in API design like Web user interfaces did in user interface design in the late nineties. Until then users were captive audience and had to put up with the GUIs we gave them. The Web liberated them and put an alternate GUI just a mouse click away. And suddenly *everybody* was doing user interface usability studies and reading books like “The Design of Everyday Things”. We are almost there with APIs, and posts like this will help make it happen.