Probably gonna be a November reveal, since Sonic is out of the way. It's up to anyone's guess on who it's going to be on the 12th November if they're keeping that trend (crossing fingers for C. Falcon because of F-Zero anniversary,) and I'm unsure if we'll get the Zelda reveal late November or early December.
Yeah, since A Link Between Worlds comes out on the day after Christmas in Japan, I think that's when either Zelda or Sheik will be revealed. It also comes out on the November 22nd in North America.
Zelda or Sheik could be revealed earlier than that, however, as Ocarina of Time's 15th Anniversary and A Link to the Past's 22nd Anniversary, and Donkey Kong Country's 19th Anniversary is on November 21st, 2013. That's an important and crazy date, given 3 of the best games ever were released on that day. We could literally get anything that day.
Oh, and for the record, DKC2, DKC3, and DK64 respectively came out on the 20th, 22nd, and 24th of November. Do with that what you will.
As for other than that, we got Mario 3D World (newcomer? stage? Yoshi? Wario?), Wii U Party (Miis? A new stage?), Wii Fit U (a Wii Fit stage=??? A male Wii Fit Trainer confirmed=???), and... well... that's about it.
Also, Super Metroid's Anniversary 20th Anniversary is March 19th, 2014. Keep that in mind, as we could get a Zero Suit Samus or Ridley reveal then. Also, EarthBound's 20th Anniversary is August 27th, 2014. Man, how many freaking amazing games came out in 1994=???
Lastly, NEW SMB Wii's 3rd Anniversary is in 2 days (a new stage=???) and Galaxy's 6th Anniversary is the 1st of November (same thing). Oh, and Melee's 12 Anniversary is on November 21st. We could definitely get a Melee veteran then.