Since this article's original posting, the one responsible for today's leak has posted several images of 3DS gameplay footage, trophies and other various screens. They can all be found here. This doesn't confirm any more playable characters, and, like the previous leak, shouldn't be considered as absolute proof until an official statement is made.
It's been a long wait for the next two entries in the Super Smash Bros. series, and there has been plenty of time for rumors and 'leaks' to run rampant. Another leak came out late last week, which seemed to confirm the complete roster, including a few new characters and notable absences. Gameplay footage was uploaded to YouTube earlier today, which may confirm that leak. The short playlist shows off an unconfirmed veteran, as well as two newcomers. Before we continue, we'd like to say that this footage, while compelling, is certainly not enough to absolutely confirm last week's leak.
The returning veteran is Ganondorf, who appears to keep the same “Captain Falcon-esque” moveset from his previous appearances, though he also seems to move a bit faster now. Other veterans featured in this video series are Pikachu, Charizard and Kirby, while previously confirmed newcomer Lucina can also be seen fighting.
As for unannounced newcomers, Shulk from Xenoblade Chronicles was confirmed by footage of his victory screen, while Bowser Jr. was shown off with in-match footage. Interestingly enough, Bowser Jr. uses the iconic Clown Car from the final boss fight in Super Mario World. He appears to fight solely from within the vehicle, which can fire cannonballs out of its mouth, and appears to extend its tongue as an attack. This certainly makes Bowser Jr. a unique character.
Given this new evidence, it's probably safe to say that last week's leak was true. If so, it means that Lucas, Snake and Ice Climbers are among the fighters that won't be returning to the fray (though the leaker made mention of DLC, though we can't confirm this yet). Additional characters included in the leak were the Duck Hunt Dog, Dr. Mario, returning from Melee and Dark Pit, who was teased in the Palutena reveal.
As for issues we had with the leak, such as the strange organization of the game's roster, it's true that what the ESRB reviewer was given may not have been the final setup. We would also like to state that, as compelling as today's footage is, we won't consider this to be 100% fact until official word is given by Nintendo. We are already seeing reasons to doubt this, such as Bowser Jr. appearing to be a clever reskin of Jigglypuff. This seems like it would be difficult to leak, though it definitely isn't impossible.