I have the two-battery, 2009 Apple Aluminum wirless keyboard. My issue is that pressing a key for an extended period of time causes it to continue to be "pressed" after I release the physical key. I got it a little over a year ago and just started experiencing problems in the last few days.
I'm running 10.8.2 Mountain Lion which disables key repeating so I only notice it when I've held down the shift lt or command keys. If I'm typing a sentence in all caps, then release the shift key, it continues to be held for a couple of second after I release it making the characters I type after stil capitalized. It's driving me mad.
I've tried replacing the keyboard, restarting, and cleaning the keys to no avail.
What should I try? Only one or two problems similar to to this on al of the web!
UPDATE: Also occurs on my Windows bootcamp partition, which means it can't be a software problem, only hardware, firmware, or bluetooth interference.