Description of problem:
I provided informations to help debugging backlight level change for various Samsung machines.
For NC10 model, after comment 40, we found out it is a LXDE problem
Thanks for filing this bug.
It is however not really a bug but more of a missing functionality. As explained in bug 861573 comment 42, LXDE does not have a power manager, lxpanel only has a very basic battery applet, so nothing listens to the keyboard events from the brightness buttons.
Feel free to file a bug in the LXDE bug tracker, but frankly speaking I think chances are low that the necessary functionality gets implemented. Therefor I recommend trying a power manager like mate-power-manager or xfce4-power-manager.
When you file a bug upstream, please add a link in the URL field so I can keep track of things. Thanks!
(In reply to Christoph Wickert from comment #1)
> When you file a bug upstream, please add a link in the URL field so I can
> keep track of things. Thanks!
An useful info:
installing xfce4-power-manager and putting it into LXDE's autostart ( http://wiki.lxde.org/en/Autostart ) solved the problem.