Ten hours, zero splats. UPDATED: Earlier start announced
UPDATE JANUARY 8: The maintenance has been updated to commence at 5 p.m. Eastern / 2 p.m. Pacific Monday. Original story follows.
The next Nintendo Network maintenance period has been announced.
"Online play, leaderboards (some online services)" are listed as being affected for both Wii U and 3DS, starting at 8 p.m. Eastern / 5 p.m. Pacific time next Monday (January 11) and stretching to 6 a.m. Eastern / 3 a.m. Pacific on the 12th.
It isn't clear what is meant by "some online services", whether that means the eShop, Miiverse or Nintendo Account functions for Japan is unclear.