I don't know whether these patches are suppose to be automated, but I should report I just fixed my brightness key for my ASUS K401J running 12.04.
$ gksudo gedit /etc/default/grub
Add "acpi_osi=Linux acpi_backlight=vendor" such that it read
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux acpi_backlight=vendor"
$ sudo update-grub2
My brightness keys finally work correctly 2 years after I first purchased it. Couldn't be happier.