Pikachu (Japanese: ピカチュウ, Pikachū) has been confirmed for SSBB. His forward smash seems longer.
Pikachu has been seen unsing Thunder, (down+B) Thunder Jolt (B), and Quick attack (up+B). He has also been seen using a Forward Smash and a down Smash.
Pikachu's Final Smash is called Volt Tackle.