Super Monkey Ball 3 is, sadly, not even in development. More inside.

According to a source close to Toshihiro Nagoshi, Super Monkey Ball 3 is not even in development. Though many websites (including this one) have posted about SMB3 and that it might include LAN play, Sega are only in the thinking process of the game, and that means no game engine, no designs, and certainly no LAN play are in development.

But all is not lost monkey fans, even being in the thinking process shows that at least there is a big chance of a SMB3 happening. Just not yet. Sorry.