Fedora 20 was released a few days ago. J.A. Watson at ZDNet has a brief overview of the different desktops available, and concludes that for the most they run just fine on any hardware, including "sub-notebooks". Furthermore, even though the "spin" of each desktop have specialised in their own applications, there are always plenty more to chose from in the main Fedora repositories.
The Anaconda installer was written back in release 18, and FedUp (FEDora UPgrader) is now the main system upgrade tool. It is not quite clear whether it is preferred to perform that on a running system though, as opposed to booting from an installer image.
Thus, the following links still apply, even for existing installations: