i think another name for 'pit' is Kid Icarus...
Link, Mario, Kirby, pikachu, samus, Meta knight and Wario are definitly gonna be in the game.
Oh, ok...
wario
snake
pit
metanight
snake
zs samus
______
/\ / / \
/ \ / / \
/ \ / / \
/ \ / \ /
/ \/ \________/
You're defiantly right about Wario, it's has been confirmed, although I don't remember the website.