Been trying to understand what Wayland entails, and sorry for my laziness, but pretty sure someone has the answer and it doesn't seem obvious from all the articles I can find. How does Wayland in Sailfish impact app compatibility? From wikipedia article on Wayland:

Does this mean all the nice SDL apps/games will not work in Sailfish? Ncurses/console based apps are most important and I'm assuming(hoping) these will work 'right out of the box' (or 'git/svn/bzr +make' kind of box)?

That's an interesting question - well, take a look here:
https://sailfishos.org/wiki/Porting/Harmattan

They clearly state SDL 2.0 support, so I hope they'll deliver it.

As stated already many linuxdist will move from X11 to MiR and/or Wayland with possible start from Q3 2014 (atleast KDE dists). Some has alphas already.

So most of those toolkits is or will be ported. Actually it is a must in the future. X11 is doomed but it will ofcourse not die 2014 but there will happen alot in this area next year is my guess.

So I do not think you have to be affraid that X/Y/Z will not be there. AFAIK terminal emulators already exists for Wayland. Also one prof of concept 3D based Qt5 terminal

lately i've been reading good things about wayland and mir ,but the question remain how does it perform compared to x11 , system resources , loading speeed , features?

All of those are pretty hard comparisons. But from the perspective of someone who has worked with both at pretty intimate levels, I'd have to say that x11 loses pretty much hands-down at all of them. x11 involves a lot more code (both in the server, and in the clients) which trickles down to harder to create features, worse performance, etc. Worst of all, there's so many moving pieces/code involved that it is not at all trivial to understand to fix bugs and improve performance.

That having been said, Wayland is pretty young and in some places immature -- and it shows. It also hasn't yet benefited from the years of debugging and improvements that the X server and protocol went through, but it is improving rapidly, and I'm sure it will continue to do so at great pace.

(full disclosure: I created the architecture for (and initial implementation of) Jolla's homescreen, as well as having had significant input/code in Nemo's homescreen -- I was also involved in early efforts prototyping the port to Wayland inside Jolla, and am still working on it now)

Started to look at some Wayland demos on utube

Here is a nintendo game in Wayland I guess those game emulators is using SDL?

http://www.youtube.com/watch?v=3ZdXu1VM_VQ

And for those who has not seen The Real Story Behind Wayland and X - Daniel Stone (linux.conf.au)

here is a thead about wayland in the top of nemo , what about wayland in the top of maemo's debian? just asking

I think SDL 2.0 works with Wayland already. Not sure about SDL 1.2 though:
https://wiki.archlinux.org/index.php/Wayland#SDL
https://github.com/soreau/SDL/tree/wayland

No idea on what stage this is with being merged upstream.

By the way, this thread belongs to the Sailfish subforum, not here.

At least SDL 2.0 is already in Mer OBS: https://build.merproject.org/package...o%3Adevel%3Amw
If I interpret the dependencies correctly this is already the Wayland version.