I'm surprised most people don't know this.
http://gonintendo.com/?mode=viewstory&id=179818
Everything moves over! Yes, even the ambassador games and title! Streetpass, play coins, unlocked content, everything!
Read my original story on Fictionpress (Shinigami Twin): http://www.fictionpress.com/s/2996503/1/Shinigami-Twin
As well as my other one (Hell's Punishment): http://www.fictionpress.com/s/3085054/1/Hell-s-Punishment
Nintendo Network ID: kingofe3