Hi,
This project might be of interest to some people on this list:
http://www.nemoux.net/
In short, it is a multi-touch window manager for Wayland, that allows
for freely rotated windows, gestures, multiple input devices and
screens, etc.
It is being developed by a few Koreans for three years now and looks
quite polished (I had the chance to try it out yesterday at the ITS
conference).
Unfortunately neither code nor binaries have been released yet.
While they plan to publish the system as open-source early next year,
they also plan to commercialize it.
Therefore, I am not really sure how open and extensible NemoShell will
be.
All the Best,
Raphael