Previously, Fedora was first and foremost a desktop distribution that also contained server elements. If all went well, the new features introduced in Fedora would eventually appear in Red Hat Enterprise Linux (RHEL). This go-around, there are three Fedora spins: one for the cloud, one for the server, and one for the workstation.
Fedora now uses a modular-style design. So, while each spin is for a specific use case, they all share the basics of the Linux kernel, RPM, yum, systemd, and Anaconda. On top of this foundation, each includes the following features:
Fedora 21 Cloud Beta
Private cloud support: OpenStack.
Public cloud support: Amazon Web Services.
Container support: Docker.
Modular cloud kernel packaging. There’s no reason to include drivers for hardware that doesn’t exist in the cloud, so Fedora 21 Cloud Beta has two kernel packages: One that contains the minimum number of modules for running in a virtual environment and a larger set for a more general installation. So the Fedora 21 Cloud Beta image is 10 percent smaller than that of Fedora 20, allowing faster deployment.
Wayland technology preview: A new display server positioned as a possible X.org Linux graphics display replacement
DevAssistant: A tool to help developers set up project environments so that they can focus on just the code and nothing but the code.
Looking at Fedora 21 as a whole, it's become clear to me that Fedora is becoming more and more an advanced look for developers and system administrators at the future of RHEL. It's always been a bleeding-edge distribution, but now more than ever, it's a distro for serious professionals rather than enthusiastic amateurs.
If you don't feel up to working with the beta, the final release of Fedora 21 is now scheduled for December 9th.