Satoru Iwata's promise that we'll see Super Smash Bros. on Wii U and 3DS drew some of the biggest cheers of E3 2011, but series overseer Masuhiro Sakurai wasn't cheering: he's not even started work on the project yet.
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. 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 even states there's not even a design document in place for the game, suggesting he hasn't even decided himself what will go into the next entry in the fan favourite fighting franchise, which puts the game a matter of years away. Don't start holding your breath just yet.