I just noticed this tonight so I'm not sure how long it's been going on, but my screen was full bright when I woke my laptop tonight. The F1/F2 keys did nothing to adjust the actual brightness even though the brightness scale displayed on the screen while the buttons were being pushed. I had not yet upgraded to 10.10.1., but I have now, with no change in behavior. A suggestion to sleep and awaken the computer did not fix the problem. Nor did a restart. Any help would be appreciated! I'm being blinded here, not to mention the extra battery drain this must be causing. I have a 13" 2013 rMBP.