Automatically Dimming the Backlight on Battery
Since upgrading my Thinkpad to the latest Xubuntu I have noticed that after 10 seconds of inactivity the display backlight automatically dimms down, which makes reading text for more than a couple of seconds pretty annoying. The question had already been asked on askubuntu.com but the answer was gnome specific and I could not find the specified dialog on Xubuntu, nor could I find the options in gconf-editor.
Ruling Out the Causes
As changing the auto-dimming level and timeout in xfce4-power-manager-settings did not fix it, I consecutively killed the xfce4-power-manager process, xscreensaver and upowerd, all without any success
gnome-settings-manager it is
Finally I stumbled over this bug report where a gsettings command is given, that will change the timeout. A quick
gsettings set org.gnome.settings-daemon.plugins.power idle-dim-time <seconds>
will fix it.
gconf-editor - dconf-editor
After that, I also found a gui to edit the gsettings database called dconf-editor, which is found in the dconf-tools package. Inside, browse to org.gnome.settings-daemon.plugins.power and you will find more settings and even get to disable the power plugin alltogether.