We'll probably get everyone from the Sal Leak.
Even if the leak is fake, with the exception of Chorus Kids.
K. Rool and Ridley look pretty promising too. Moreso K. Rool.
And Mewtwo if he counts. ESPECIALLY Mewtwo.
So I wouldn't worry about hype characters. There's a lot more to be revealed.
On another note, check out my Chorus Kids moveset!
Keep this in mind as you read: each attack triggers a 4/4 time signature metronome, to assist in keeping the beat.
B: Glee Club
The first Chorus Kid starts to sing, and pressing B in rhythm allows the other two to join in, sending blue shock waves in three directions. B can be held after the last kid joins in, which forms a sort of barrier around them. Letting go sends the sound waves shooting in their respective directions.
Side B: Love Lab
The Chorus Kids sway to a quick rhythm, passing a chemical-filled test tube down the line. Pressing Side-B in rhythm keeps the beaker moving, but losing the beat makes the kids drop the beaker. The last kid in line tosses the chemical to his side, hopefully hitting an opponent, and granting an effect. The chemical's effects are in a set order: Burn, Freeze, Pitfall (ground)/Meteor Smash (air).
Up B: Micro Row
Holding down Up-B causes the kids to be squashes down, and letting go causes them to shoot upward. Pressing Up-B in rhythm allows them to do this three times.
Down B: Tap Troupe
This attack's function is similar to DK's Down B. The Chorus Kids tap dance by stomping on the ground, causing a quake in the area surrounding them. To continue tapping, Down-B must be tapped in a syncopated pattern. Each round of tapping is completed by a powerful stomp. The tapping causes a quake with low knockback, while the stomp can send your opponents flying.
Final Smash: Rhythm Paradise
Much of the Rhythm Heaven cast comes in and tramples the opponents. Get creative with this one, imagine it yourself.
I personally imagine the Wrestler being among the cast on the ground, and the Blue Birds hitting the opponents from above.
And check out their support thread when you have the time.
I hear the guy who owns it is real cool.