To be fair, Wayland seems similarly hopeful about shipping in Fedora 23, which is only 4 months before Ubuntu 16.04. Also, Canonical has a big incentive to ship Mir in 16.04, since it's a long term support release. If they don't make it, they'll be forced to support X for an extra 5 years.
I think both projects have equally "hopeful" (slim) chances of hitting their dates. If they do ship on time, I expect stability and features to suffer.
Wayland has been around, I think, at least 3 years before Mir's announcement, though. It's had plenty of time to evolve naturally without any fixed corporate goals necessitating them to act fast.
It's also worth noting that many of the changes required when switching out the display server (moving stuff out of X and into the kernel, adding features to drivers) was done while developing Wayland. Mir doesn't have to worry about this stuff, so they should be able to do it much quicker than the time it has taken Wayland to mature.
I cant seem to find a .deb + bleeding edge Gnome system anywhere. Ubuntu Gnome is what I use right now, but Fedora 22 is so good that it is making me jealous.
I would pay money to get a Debian based Gnome distro which is constantly updated. And now that is even more critical as Ubuntu goes off in Mir territory while the rest of the world go to Wayland.
I tried to get on the Debian bandwagon, but it is so unfriendly that it is not funny. I know it is built around a philosophy, but I seriously encourage everyone to try out Fedora 21 Workstation to really see what a great Linux experience can feel like.
