While stable kernel updates are common in the Fedora Linux world, Mesa releases tend not to be, but generally there are new Fedora releases every six months. Mesa also used to be on a six month release cadence but now it's onto a three month cycle while Fedora 21 will arrive nearly a year after Fedora 20 due to major restructuring within the Fedora camp. With Mesa 10.1 now being the latest release and Mesa 10.2 under full-development, it's becoming harder to back-port fixes to the Mesa 9.2 series that Fedora 20 is still shipping.
A FESCo ticket was opened this week about getting Mesa 10.0.3 into Fedora 20 as a stable update in order to fix a Mesa/RadeonSI issue. "There no broken API/ABI, only added functions, refactoring, etc. There was 10.0, 10.0.1, 10.0.2, 10.0.3, 10.1. I can confirm - it's stable."
Red Hat X.Org developer David Airlie seems in support of this move with having an updated Mesa and updated VMware DDX driver (due to the XA Gallium3D state tracker used by the VMware driver having an ABI bump) in testing for F20.
With having clarification today from the Fedora Engineering and Steering Committee, it looks like Mesa 10.0.x will end up making its way into Fedora 20 as a stable update, which is great to see given there's OpenGL 3.3 support and many other new improvements/features, including performance optimizations. Right now Mesa 10.0.3 is in Fedora 20's updates-testing; Mesa 10.1 for Fedora 20 isn't being talked about at this time, but those wishing to find more recent Mesa 3D packages for Fedora 20 can utilize this Copr repository. Fedora 21 with a fully-updated open-source Linux graphics stack looks like it will come in October or November.
Update: It looks fairly certain now that Mesa 10 will land in Fedora 20 updates soon as it clears updates-testing.