Apparently the development team may announce another game soon:
"Koichi Hayashida and Yoshiaki Koizumi have told Spanish publication El Pais that they can’t disclose their next project, but they should make an announcement soon. Koichi Hayashida said that the team is currently wrapped up in Super Mario 3D World and was asked whether or not they were planning to release downloadable content for the forthcoming Wii U game. Hayashida said quite clearly that it’s not something they are looking to do at the moment. Here’s what they both had to say."
"Koichi Hayashida and Yoshiaki Koizumi have told Spanish publication El Pais that they can’t disclose their next project, but they should make an announcement soon. Koichi Hayashida said that the team is currently wrapped up in Super Mario 3D World and was asked whether or not they were planning to release downloadable content for the forthcoming Wii U game. Hayashida said quite clearly that it’s not something they are looking to do at the moment. Here’s what they both had to say."
Q. Some believe that the downloadable content is back to pay for something, is this title, as the current Wii U, will have this option?
KH. For now we have no plans in that direction.
Q. What is your next job?
KH: At the moment, Super Mario 3D World, 100%.
YK: I can not disclose now, but soon we will make an announcement.