Amazon's plan to make a gamepad has been leaked. As the images from Dave Zatz (Brazil's equivalent of the FCC), the chances are high that these images are not fake.
The controller consists of 4 action buttons A,B,X,Y with 2 analog sticks, a directional pad and four function buttons in the center. Towards the edge, Amazon provided media controllers. The controller uses two AA size batteries.
What's uncertain is that the purpose of these controllers. It is speculated that Amazon might have made this gamepad for Kindle Fire's GameCircle service. It could also be possible that this could be a part of Android powered gaming console that Amazon's probably working or. Seeing that there are basic media controls, it may be for an upcoming set-top box unit with an inbuilt gaming console.
As of now there is now official statement from Amazon, or any idea about its future products that will use the gamepad. Stay tuned for more updates.