Comment 4 for bug 947748

Same here.

The brightness controls on my MacBook Pro stopped working. The pop-up
that usually shows the brightness level does not longer pop up, and the
keys that adjust the brightness don't work anymore.

As a side note, the keys that control the keyboard backlight still work,
however the pop-up indicator does not change which each keypress, no
longer indicating the keyboard light level as it did only yesterday.