This is a total restructuring of Linux and how it handles displays. Total restructuring.
It's taking stagnet and obsolete design that is stuck in the 1980's and getting it competitive with the latest and greatest that any other display system has to offer. And not only just for accelerating GUIs...
efforts to take advantage of those high speed floating point co-processors for general Linux programming is tied into it. Currently it's impossible for Linux folks to take full advantage of their hardware processing power using fully open source means.
Basically all if this would take much too long to accomplish without the assistance of the distributions and user base. Users are free to use systems like CentOS/Redhat/Debian Stable if they don't want to run into problems on production machines.