I don't think it's been addressed yet, but I'm curious how the system would react if your power went out. Would it assume the system was unplugged from the dock then? I like the idea of not losing my game progress with a sudden power outage. I myself have battery backup on my internet and router so I like the idea if I was playing online and power went out, i could continue playing without issue

Nothing has been said about battery life in the joycons either, or the other controller options

Reports are 20 hours for the Joy-Con and 40 hours for the Pro Controller.