For those of you predicting characters, there is one thing you can always figure out looking at this page http://www.smashbros.com/en_us/list/index.html
We seem to never get 2 character updates in a row unless they are on the same day. Our last update was a character update, so tomorrow's won't be a character. We also just got 2 items (1 assist trophy and 1 pokemon), so it's most likely not either of those.
That doesn't leave much, so I'm guessing we'll get the stage Norfair.