Smash Bros. Brawl by the game's official blog. However, don't expect to be playing as the hulking mound of muscle and tiny sunglasses. He's one of the first characters who'll be summoned up by "Assist Trophies," which you can read more about here.
Also confirmed to be locked away in the glass domes (we assume there are air holes) are one of the Hammer Bros. and a Nintendog. While we think it's great to include some ham 'n' eggers in the mix for a single attack without having to fully flesh them out, we'll reserve judgement until they stuff Tingle into one of those things.
Read -- Samurai Goro
Read -- Assist Trophies