Here's my list:
Dr. Mario-Costume.
Pichu-Kicked out the door and thrown to a pack of wild coyotes.
Roy-Gone or AT'd.
Marth-In.
Falco-In with new moveset.
Sheik-As much as noobs like all my friends abused her, she's AT bait.
Ganon-What's wrong with you people, of course he's in!...With a new moveset, of course.
Jigglypuff-One of the 12, he/she/it is in.
Ness-Has been on a two month trip around the world, hunting down and murdering Lucas and his family.
Luigi-New Moveset, still in.
Captain Falcon-He's in, though I'm not too crazy about it myself.
Ice Climbers-They were original and retro, so I hope that they're in.
G&W-He's the star of the very first Nintendo system, however sucky he may be, he's in.
Mewtwo-He's in, since Deoxys didn't finish him off.
Young Link-He's Cel-shaded, and given a new-ish moveset, still in.