I thought the issue was deemed almost a non factor in 99.99% of all shooting situations assuming you had a lens on the camera, shooting with your eye at the VF and the lens cap off the lens... not worth holding off on a purchase if you ask me
The camera is performing within specifications.
Don't believe me? Try it yourself.
From the horse's mouth:
EV 1-20 (at 73°F / 23°C with 50mm f/1.4 lens at ISO 100)
EV 1 @ f/1.4 @ ISO 100 is a one-second exposure. I just mounted my 50 f/1.4 and found a dark corner of a room to aim at that had the meter bug pegged in the middle at those settings. Turning the light on and off resulted in no change in measured exposure. At two seconds (and a darker part of the room), no change in exposure. Finally, at four seconds (EV -1, well below the spec), the light caused a third of a stop of error.
Still a third of a stop at eight seconds, and flicking between a third and two thirds at fifteen seconds -- and I was only able to get it down to fifteen seconds by partially covering the lens hood with my hand. When I had the lens hood mostly covered, I could get it down to 30", and the error was solidly two thirds of a stop. And anybody who thinks they've got a photographic light meter (built-in, hand-held, whatever) that's useful at EV -4 is nuts.
Oh -- and ambient temperature is 77°, in case you're wondering.