The Amazon Kindle Fire tablet is on it's third iteration, but the first generation Kindle Fire is still alive and kicking. The fact that it's extremely hackable has kept developers and users coming back to it. At this point in its life it is very inexpensive too. You can probably find one used or refurbished for less than $100. The tablet comes with Amazon's Fire OS loaded on it. If you're like us, you don't want to be stuck using Amazon's ecosystem. Have no fear. Devs have gotten CM11 up and running on the original Kindle Fire.
CM11 is based on Android 4.4 KitKat, so not only is the first gen Kindle Fire getting updated firmware; it's getting updated to the latest version of Android. A developer who goes by the handle FuZZ__ has compiled an unofficial build of CM11 for the Kindle Fire that he calls Kitkang. It's housed on the Euroskank website. You can also track development on this XDA Forums thread. There's even a first gen Kindle Fire toolkit on XDA to help you root the device and install a custom recovery. You'll need those before you can install this unofficial CM11 build.
The performance of this CM11 Kindle Fire build is still in the early stages. There may be some bugs. Early testers report issues with graphics not being smooth. The stock web browser also tends to crash. Most things work without a problem, though. It's still a work in progress, but it runs and it's usable.
Amazon isn't ever going to release a clean, stock-Android build of 4.4 KitKat for the Kindle Fire. They probably won't ever release a KitKat Fire OS build at all. Google isn't going to support Amazon's hardware or their Android fork either. Running a custom ROM is going to be the only way users will ever get an Android 4.4 update for this tablet.
The development work for the first generation Kindle Fire reminds me of the dev work for the HP TouchPad, after the TouchPad was discontinued. Android developers kept the TouchPad alive for years. The first gen Kindle Fire could be kept around for a lot longer than Amazon ever planned, thanks to amazing devs like FuZZ__ and others like him.