I have exactly the same problem and unit and was on the phone for over 40min trying various things with no resolution other than they would investigate further and then I received the below from Amazon.
I'm sorry for the troubles you've had while trying to use your Kindle for Android application.
Further to our conversation, I just want to let you know that the reason behind the issue you have experienced with your Kindle for android application was the origin of the Market where you have it downloaded. It needs to be downloaded from a Default Market which should be pre-installed already into your tablet since then, it appeared that you have downloaded the application from a Market, not a pre-installed one, which is not a supported.
I have replied to the the above with.
After looking on android forums I see that last update of your kindle app excluded the Wondremedia 8650. My device was originally registered using the authorised app from Google Android Market and now I cannot find the device other than a quick flash before it goes to registeration page.
You control the app and you took my money for downloads which I can no longer access. I will give you the opportunity to reply before taking advice.
