It has been confirmed that Super Smash Bros. for 3DS will take advantage of the "new" 3DS' C button.
This news will no doubt be divisive among the Smash community, as the C stick is used in Super Smash Bros. to immediately pull of a powerful move called a Smash Attack. Many players feel using the C Stick for this is a big no no, while other players swear by it.
So, for those of us with standard 3DS models, we'll have to get used to mastering Smash attacks in the "traditional" way. Super Smash Bros. for 3DS is our October 3rd.