OK, I have been using GO Launcher for about a month now.
On a different ROM, but you know... It's still the same hardware.
Have you guys ever thought, that there is a slight possibility, besides the typical "Oh, Amazon just doesn't want us to use it and force the bookshelves on us" remark, that MAYBE there is some other issues with the launcher when used with the Amazon build? Which is why it's not officially listed as being supported anymore?
Amazon really, really made huge changes to the stock ROM, so much that they've overridden a lot of the default Android stuff to make it work for them. There are issues with GO Launcher when paired with the default Kindle setup, and that's a fact.