It has been confirmed by Nintendo that Mewtwo is going to be DLC for both versions of Smash 4, available in spring of 2015.
It has been shown here: www.idigitaltimes.com/super-sm…
I would also suggest watching the video on that page for Bowser Junior's formal intro video. It's fantastic. I find it hard to believe that a lot of people actually didn't want Bowser Jr. to be a smash bro. Like, why? I mean I can understand not caring for his inclusion, but to down-right detest his presence? I mean, I admit I'm a little sad he doesn't fight on foot, but that's made-up for with his amazing costume swops. Duck Hunt Dog though? That's another story...
So, that's pretty cool and HOLY SHIT look at that stage builder! What an improvement!!
With the new "Danger Zone" feature, I can totally make an awesome "Lost City of Lowrule" (of The Wonderful 101) stage! I freaking love fire levels!
And, with the confirmation of Mewtwo as DLC, this brings the possibility of other characters as DLC to the table.
Good... where's my Wonder Red and Lucas?
The way Lucas hasn't even appeared as a trophy suggests to me that he's pretty much undoubtedly going to be DLC. Wonder Red's chances on the other (unite!)hand still look grim. Ugh... Well, where's my Lukie-cake?