I'm not sure when this happened (sometime in the last few days) but the Ambient Light Sensor stopped working on my 15" AlBook. When I turn the lights off, my screen used to dim and the keyboard would light up. When I turned the lights back on, the keyboard would unlight and the screen would brighten. This no longer happens. I checked my preferences and both features are still enabled. I also tried shutting down my computer and restarting it just in case there was a daemon that had died or something. OMG, as I was typing this, I held my hand over the grill on the left of the keyboard for a second and the screen brightened a little bit. I decided to try the "turn the lights off" thing again and it works. Has anyone seen this happen where the ALS system stops working for a few days and then just starts working again? Could it be dust getting in the grills on the left and right of the keyboard?