Japanese site Niconico is blocking out an hour of time for the Nintendo Switch presentation according to Nintendo Life. The presentation, which airs in America 8 p.m. PST and 11 p.m. EST on January 12th would be one of Nintendo's largest presentations if true!
I'm assuming that in addition to the long-awaited hardware specs of the console we're also going to see plenty of gameplay footage from games both announced and unannounced. An hour is about the length of your typical E3 presentation and most console launches are announced around those presentations so I'm inclined to believe it.
I've read some speculation that the Nintendo Direct will exceed an hour...but I don't take much stock in that. If it does go over it'll be by minutes...there's just not enough and hardware specifications will fill 10 minutes max. Anyone staying up late like me to watch the reveal this Thursday?