Coming from IGN's Nintendo Voice Chat podcast...
- project was lead by Yoshio Sakamoto
- Sakamoto was deeply involved in Tomodachi Life as well
- Nintendo won't talk about the Miitomo dev team size or how long the app was in development
For those that don't know, Mr. Sakamoto is most well-known for his work on the Metroid series. It seems he's taken to more social projects in recent years.