Switching from KDM to LightDM login manager
As it is possible to compile
kde-workspace without KDM using a cmake parameter , we can replace the default KDE login manager (KDM) with others, namely LightDM that has improved its KDE support dramatically lately.
- Code base - more recent, supports multiple graphical backends as Ubuntu just announced Mir (so adding Wayland eventually will be easier)
- In comparison, KDM contains major portion of code of XDM which means the backend is basically pure C communicating with the C++/Qt frontend. Many very handy facilities for managing X are missing, not mentioning the fact there is going to be need to support Wayland in future.
- Better performance (according to their presentation, my experince so far is not that great - mbriza) and "light"
- I'm a bit sceptical about this point, will measure precise memory and CPU requirements in the future..
- Simpler API for creating greeters
- Powermanagement is present
- Although it is present, is it really a pro as we'll be adding an other powermanager separated from PowerDevil? The settings would differ or would need to be propagated. Also, it's now provided by systemd, too. Will have to investigate further.
- Multi-head support is better - Prompt is displayed on the screen where the mouse cursor is
- solved: Switching users in KDE is not possible. 
- Dependency on glib
What needs to be done:
- Add the conditional KDM inclusion parameter to
kde-settingsnot to ship KDM settings
- http://www.freedesktop.org/wiki/Software/LightDM official web
- http://www.sharpley.org.uk/node contains release info and interesting discussions (unfortunately there are no tags to filter the articles)
- http://lists.kde.org/?l=kde-core-devel&m=130799230315640 a quite lenghty thread comparing KDM to LightDM in the KDE-core-devel mailing list
- http://mjg59.livejournal.com/136274.html An article describing why it maybe is not such a good idea to switch to LightDM