Minecraft Pocket Edition is finally available on the Amazon App Store, which by proxy means that it can easily be purchased on your Kindle Fire and installed in minutes.
Although a large number of people have already rooted their Fire months ago just so they can play Minecraft, you non-rooters out there will probably be pleased at the new ease of installation. For you sticklers out there, this build is the current version of Pocket Edition.
If you're ready to spend money, you can nab it for $7. Or you can just visit the product landing page and watch people argue over how much better Block Story is -- your choice.