It appears Mir is prime time and ready to go in the next Ubuntu release.
Ubuntu 13.10 to ship with Mir instead of X
It makes me wonder how this will affect Linux Mint? Will Linux Mint eventually dump using the Ubuntu repositories and maintain their own? Or perhaps go back to using Debian repositories?
Also it appears most of the KDE and Gnome/Cinnamon/Mate developers are developing for a transformation to Wayland and not Mir?
Definitely more questions than answers concerning the Mir / Wayland / Xorg situation.