Gamerace on 06 April 2009
What - the usual, more characters, balance, levels, more robust level editor and online that actually works
Who - Little Mac, Isaac (Golden Sun), Crystal (Star Fox), a Magic user from Fire Emblem, Miis
I wouldn't expect many if any additional 3rd party characters. 2 at the most. And for those I'd have to go with Cloud (SE) and Megaman (Capcom) being the most obvious to include. (Cloud appeared in Mario 3 on 3 basketball)
