Please do not answer this if your not sure if your right ok here goes.....

None have been confirmed. However, don't get your hopes up about roy and marth(because of the addition of Ike) and Dr.Mario (because they've been getting rid of duplicate characters).

The following characters have been officially confirmed. Mario, Link, Kirby, Pikachu, Fox, Samus (with Zero Suit Samus), Zelda, Bowser, Donkey Kong, Yoshi, Peach, Ice Climbers, (Newcomers) Pit (Kid Icarus), Wario (WarioWare), Ike (Fire Emblem), Pokemon Trainer (using Squirtle, Ivysaur, and Charizard), Diddy Kong (DK), Meta Knight (Kirby), Snake (Konami's Metal Gear), Lucas (EarthBound), and...the moment you've all been waiting for...SONIC THE HEDGEHOG!!!

The following characters have been officially confirmed. Mario, Link, Kirby, Pikachu, Fox, Samus (with Zero Suit Samus), Zelda, Bowser, Donkey Kong, Yoshi, Peach, Ice Climbers, (Newcomers) Pit (Kid Icarus), Wario (WarioWare), Ike (Fire Emblem), Pokemon Trainer (using Squirtle, Ivysaur, and Charizard), Diddy Kong (DK), Meta Knight (Kirby), Snake (Konami's Metal Gear), Lucas (EarthBound), and...the moment you've all been waiting for...SONIC THE HEDGEHOG!!!

Roy and Marth are most likely not going to be in it, but you never know, no one really knows about mewtwo (I sure do want him back; I rock with mewtwo), Waluigi should be in it, but he's already an assist trophy, so no, he isn't a playable character, Dr. Mario isn't going to be in it, since they're getting rid of duplicates, sonic is one of the only third party characters that's going to be included (if not the only), and as for shadow and knuckles, I'm 99.99% sure that they are not in this game.

Sonic is coming. Waluigi isn't due to him being an Assist Trophy.

Newcomers:
- Pit
- Wario
- Samus/Zero Suit Samus
- Ike
- Pokemon Trainer
- Diddy Kong
- Meta Knight
- Snake
- Luca
- Sonic
- King Dedede
- Pikmin & Olimar

Veteran Fighters:
- Mario
- Link
- Kirby
- Pikachu
- Fox
- Zelda/Sheik
- Bowser
- Donkey Kong
- Yoshi
- Peach
- Ice Climbers

Secret Characters known so far:
- Ness
- Marth

Source: http://www.smashbros.com/en_us/characters/index.html

Sonic is going to be in the game. Waluigi is an assist trophy. Marth is a hidden character.

Marth and sonic are going to be in brawl but roy mewtew shadow ect. Are not sorry.

Mewtwo will not be in the game
He was replaced by Lucario

Roy will not be in the game
He is replaced by Ike

Marth will be in the game

Dr. Mario will not be in the game

Shadow and Knucles will not be in the game

Those characters are not in Super Smash Brothers Brawl. I am sorry but they will not be appearing.

Mewtwo is not returning.
Roy is also not returning.
Marth is returning.
Waluigi is not playable,but an Assist trophy.
Dr. Mario not in it.
Sonic is in it.
Shadow is not playable,but an Assist trophy.