This. So much of this. Mir will plow on regardless. If it doesn't work in 14.04, Canonical will continue to push it until it does work. As they did with Unity. I dare say that if Wayland isn't right in Fedora 21, many people won't give it another chance for a long time.

If you follow the Wayland development process you will see that there is no rush at all. They have used the last five years only to come to version 1.0 of the protocol.
It is already clear (and Canonical has already announced that) that Mir will not be ready for 14.04. Canonical's plans currently are:
- 13.10 will have Unity 7 running on XMir, but will fall back to Xorg if you (have to) use the proprietary AMD/Nvidia drivers
- 14.04 LTS: Unity 7 on XMir, no fallback to Xorg anymore, Canonical assumes that they will have proprietary Mir drivers at this point, let's see how that works out
- 14.10: Unity 8 (the first Mir native version) running on Mir.

Two things two keep in mind:
- Running Unity (or any other DE/WM) on XMir has no advantages at all, but is only done to force Ubuntu users to be beta testers
- XMir, at least at the current state, is not able to run X applications under Mir (no rootless X), it is solely used to provide a fullscreen window to run DEs/WMs, contrary to XWayland, which can run X applications under Wayland, but can not (and according to the developers never will) run DEs/WMs

That Canonical will continue to push Mir also will not change the technical problems that other DEs and WMs would have to port their compositors to it. Martin Gräßlin, the main developer of kwin, has some very good articles about these problems in his blog, worth a read for anyone interested.
I do neither use Ubuntu nor Unity and as it seems those will be the only options for Mir, so I don't see any point in supporting it. YMMV.

A very biased opinion here says otherwise on 13.10 Beta -> http://www.markshuttleworth.com/archives/1269

"I’m nonetheless surprised that the system feels *smoother* than it did pre-Mir. It might be coincidence, Saucy is changing pretty fast and new versions of X and Compiz have both landed while I’ve had Mir running. But watching top suggests that both Xorg and Compiz are using less memory and fewer CPU cycles under Mir than they were with X handling the hardware directly."

Less memory and fewer CPU cycles is an advantage. But, I don't know how this would translate to other DE/WM.

Would be interesting to know if the memory and CPU load you see removed from X/Compiz magically appear in Mir's top entry. And a smoother feeling is not something reliable at all. Technically it makes absolutely no sense to add a layer to the graphics system just because you can.

EDIT_ Shuttleworth's statement is also contrary to these benchmarks: http://www.phoronix.com/scan.php?pag...lle_xmir&num=1

I suspect this would be the case. A lot of weasel words were used. Like "system feels smoother".

And since when do we trust weasels?

I don't. There is no technical reason at all for Mir's existence. So far I can see only one reason why Canonical does not use Wayland: licenses.
While Wayland, like Xorg, uses the MIT license, so that anyone can make and sell a derived work, Mir uses GPL3 together with Canonical's Contributor License Agreement (CLA). This CLA gives Canonical the right to re-license Mir under any license they want. This enables Canonical, but none of their competitors, to sell Mir under a different license to companies that don't want to use the GPL licensed version (and in general it seems that most companies in the mobile sector are not fans of the GPL3), giving Canonical an advantage over their competitors if Mir gets traction in the mobile sector.

Without driver support Mir won't get far.

It works (at the current state there seem to be problems with the radeon drivers, but Mir is still in very early development) with the FOSS drivers, but Canonical/Shuttleworth claim that they will get support from AMD/Nvidia. There were no statements from them that I know of, but eventually Mir will get driver support, at least when those companies release Wayland drivers, since those should automatically be compatible with Mir. If this will be the case for 14.04, as Canonical claims, I don't know, but my experience with AMD's driver development speed lets me think that this is unlikely.

It more than likely won't.

The FOSS drivers are one thing, but Proprietary drivers are completely another ball game.

As far as being automatically compatible between Mir and Wayland, it might look good on paper to say that, but in practice trying to support two architectures that aren't on the same page in development is a perpetual nightmare. Both projects would have to share a common code base for architecture and API, and they do not.

Even Jonathan Riddell of the Kubuntu project said that Kubuntu would be avoiding Mir in favor of X.Org until Wayland was complete:

http://blogs.kde.org/2013/06/26/kubu...ng-mir-or-xmir

This is like DirectFB and Y-Windows all over again. Something to try and replace X.Org but not doing it incorrectly, too fast, too rushed, and over-hyped breaking everything...

...and we though Canonical learned their lesson with the craptastic job they did with PulseAudio...

...but apparently, they have not.

Driver wise they actually do have most things in common, both will use the EGL driver standard (with one extension for Wayland), so if a Wayland driver occurs it should work for Mir. Sadly it isn't the other way around, but since Wayland is designed to be able to switch the driver backend (for example, with libhybris you can use Android drivers) this is not that much of a problem.

But yes, you are right, Canonical really seems to have a problem with releasing stable software, but I think that is due to its short release cycle and its heavy marketing: They always need buzzwords and features for the next release, so that they constantly are discussed in blogs and never slip out of the public sight. That this costs them their quality (by the way for me the main reason to leave Ubuntu when 10.04 was released) does not seem to matter for them.

Quality is one thing that can make or break a distribution. Sure there is always the following a distribution will have and those who will swear by it, even if everything ends up broken like ArchLinux tends to do from time to time, but even then you have to have some level of quality control on the retail version control end so that whatever you do in -Current trees, can have a free period of stability checks and testing to make sure you get it right without nuking the OS and having to start all over again rebuilding the tree branch to make sure everything is compatible and stable.

The difference between Ubuntu on one side and Arch or development branches of stable distributions, like Debian Sid or Slackware -current (though -current is still exceptionally stable), on the other side is that the users of the latter know that they will get unstable behavior or a broken system from time to time, that is simply the price to pay for living on the edge and they are prepared to handle that, while Ubuntu users get releases that pretend to be stable, while they are in reality released with bugs just because they can't move the release date due to the heavy marketing. If even their "enterprise grade" branch, the LTS versions, tell their users not to upgrade from previous LTS versions before the first point release then there can't be any other conclusion that this release model is seriously broken and incapable of delivering a stable system.
With removing the Xorg fallback in 14.04 and being totally dependent on XMir, an unnecessary additional layer, Canonical even degrades their LTS users to nothing more than beta testers.

One thing you NEVER do to end-users of a an Official release of software is to make the end-user nothing more than a Beta Tester.

I've seen companies of all kinds get a heavy handed slamming by their users and critics over that exact practice, and why very few to this day will release untested, unstable, and bleeding-edge software to the end-users without some level of warning.

Canonical is playing with matches in a room full of Gunpowder barrels. It's only a matter of time before something bad happens.

Which version of KDE will 14.1 ship with? I've noticed the acknowledgement of 4.11 but also that it might be a bit too new.

Unless we get 4.11, I suppose there isn't a lot of point in Wayland being in /extra this time. I am fine with that. I suppose that would be more and an incremental release though. For 15.0 I would hope to see 'some' Wayland support even in /extra, but I guess that is still a while off. I would be interested in seeing Wayland in action though.