If you're not familiar with the GLX rewrite that's going on for the X.Org Server, see The X.Org Server's GLX Is Being Rewritten, it was covered at XDC2013. The patch-set rips the fork of GLAPI out of the X.Org Server and converts the GLX code into communicating with the OpenGL library (libGL) directly. In the end this will allow the X.Org Server to better utilize OpenGL within the X Server itself.
The GLX dispatch rewrite announcement on the X.Org mailing list can be found in this thread. The GLX rewrite is a potential feature for X.Org Server 1.15 but its feature merge window will close soon so it might not end up landing until X.Org Server 1.16 in 2014.