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Fedora is also looking at a switch to Wayland, though obviously not right away. Some informative posts from the mailing list thread by Adam Jackson:

On Tue, 2010-11-09 at 11:44 -0500, Gregory Maxwell wrote:

> I think we'd like to see the Fedora community figure out its position
> on the subject— so that it can tell the Wayland developers "If you
> continue on this track, then as things stand, Fedora will not be
> making it a part of the default Fedora install".

Well, the Fedora graphics cabal is basically me, Kevin Martin, and Dave
Airlie, and since we were hanging out at Plumbers last week and talked
about this, here's the rough consensus I think we reached:

Wayland's not a usable default yet. It'll probably be packaged in F15
as something you can play with. We don't even have a complete list of
transition criteria yet, let alone a timeframe for switching the
default. But it's likely to happen eventually because it's a serious
win for a lot of things, and the downsides are pretty negligible despite
the fear from the peanut gallery.

Feel free to quote me.

- ajax

On Tue, 2010-11-09 at 17:40 +0000, Andrew Haley wrote:

> I'm wondering of I'm reading this correctly. The downsides that have
> been described are quite severe in contrast to the possible benefits.
> It is, of course, possible that a mistake has been made, and the acute
> loss of functionality is just scaremongering. It's also possible that
> I've misunderstood something.

The downsides that have been described include:

- We lose network transparency! Well, sure, the protocol doesn't have
that directly. You can still do vnc-like things trivially and with a
modest amount of additional wayland protocol (or just inter-client
conventions) you can do spice-like things. This is good, not bad,
because efficient remoting protocols do not look like X. Now we get to
design a good one, and in the meantime vnc-style remoting sure does go a
long way towards being good enough. (But, we can't switch yet, because
we don't even have vnc-style remoting yet; so we're not switching yet.)

- We lose support for older hardware! Yep. Here's a nickel. We have
sufficient kernel support for this for the big three hardware vendors,
and we're probably going to see more ports to the marginal hardware in
the next year or two. Losing <1% of the hardware support isn't keeping
me up at night. (But, we can't switch yet, because there's not a good
fallback design to classic X on that kind of hardware, and it includes
things enterprisey people run on; so we're not switching yet.)

- All my X apps have to be ported! Yes, if they want to be native
wayland clients, they do. If they don't, you can run a nested X server
like on OSX. They'll still work as well as they ever did, and you even
get to keep ssh forwarding of them. You can run a wayland server that
does nothing but run a nested X server and you wouldn't ever know the
difference. Except of course that your shell and your screensaver can
be wayland apps, which means your screen locker will still work even if
an app has a menu open, and you can actually do secure password input,
and and and. (But, we really don't have _any_ good native wayland apps
yet, thus the benefit of native apps are at the moment theoretical; so
we're not switching yet.)

Anything I'm missing?

- ajax

On Tue, 2010-11-09 at 14:01 -0500, Brian Wheeler wrote:
> On Tue, 2010-11-09 at 13:47 -0500, Adam Jackson wrote:
> > And I'm saying you can get the network remoting effect you like in X, in
> > Wayland. It's not built into the local Wayland rendering system, but
> > there are both trivial ways to add it (vnc-like) and complicated ways to
> > add it (rdp-like) and both will work.
>
> So would it be a rooted VNC? If so, that simply sucks. The rdp style
> is better, but I have a sneaking suspicion that it is going to be hit or
> miss in different toolkits the same way that GUI/TUI admin tools are
> always "kept in sync".

Sorry, I assumed a bit much domain knowledge here.

When I say "vnc-like" I mean "let's scrape the pixels out of the
rendering buffer and shove them over the wire". VNC itself is rooted,
but vnc-like remoting can be rooted or rootless. In wayland the
fundamental object of composition is a whole window, so you have
scrapeable surfaces both at the window level and at the top level. Take
your pick.

When I say "rdp-like" I mean "instill enough awareness of the
possibility of remoting in the rendering system that remoting can send a
rendering command stream instead of raw pixels if that seems to be a
win". Wordy, I admit. And, obviously, much more work than just
vnc-like scraping. But it's a serious win for WAN links, and is the
only viable way to remote 3D, etc.

And, of course, you can have both at once. rdp-like remoting probably
requires toolkit awareness (in this bizarro world, the nested X server
counts as a toolkit!), so if you end up remoting an app that lacks that
level of toolkit support, you can fall back to vnc-like.

- ajax