A lot of Nintendo-fans were probably very excited after the Nintendo media briefing at E3. Not only because of the Wii U announcement, but also because Satoru Iwata mentioned a Super Smash Bros coming for the console at some point in the future.
Don't hope for a launch title, though. Actually, don't hold your breath at all. 1up have transcribed a column from Famitsu, written by creator Masahiro Sakurai who says that they are focusing solely on Kid Icarus right now. "We've got no plans whatsoever - we've got two new games out in the open when there's no extra time to work with them at all", Sakurai writes. "It makes me cringe, and I'm not sure it's the smartest thing to make gamers wait for several years, but the early announcement was made chiefly in order to attract new team members."
Sakurai seems rather stressed at the idea of a new Super Smash Bros-game. "With previous projects I had a game design document in place before forming a team, but with this I don't have the time for that. I won't be able to look at every aspect of the game and balance out all the characters by myself this time. I'm trying to think about how this is going to work out, but probably I'll have to discuss it with my future development team. The future of this project really depends on the people I can get involved with it."