I noted this in the other thread, but this happened for the first time to me yesterday (or was it the day before?) Either way, I've seen it 4 times in the past couple of days now. My car is set not to power down the displays, yet it does after 30 minutes or so. I'm seeing more and more reports of the black screen issue. I'm wondering if we're seeing something that is becoming more pervasive in v4.1, due to something that is persisting in storage (since soft reboots aren't fixing it).
EDIT: Now that I think about it... 2013 bug perhaps? Seems to have started Tuesday for a lot of people?