With our flight scheduled to get in 5 hours after its original time, the people who got affected the most were people that were trying to make connecting flights. They'll be set up with hotels and shuttled to and from the airport.
In my case, the original plan was to clear customs, pick up my wireless hot spot, pick up my JR Pass, get some local currency and head into Tokyo to check into my hotel by around 7 pm.
All of these plans will look different. I can only pick up the hot spot, if the post office is open. I'm trying to find out from the company what they've done in cases like mine. The JR office will also be closed so I won't be able to get my pass until Sunday. Local trains will be running, but they might be offering shuttle service into Tokyo, so I'll likely or hopefully be able to check in before midnight.
Whew.
Thankfully the airport terminal has a number of "powered" seats that have AC and USB plugs and ports respectively. Otherwise I would have ran down my phone during the flight.
Only 2 more hours until check in.
-- wake .eat.sleep