According to JeuxFrance, Nintendo Power, the official magazine has come up with more details about the much-awaited New Super Mario Bros. on the DS that's slated for release this may in the US and Japan.

It says that the New Super Mario Bros will have no less than 80 levels! It will be a return to the basics for those who are not aggressive gamers and more traditional in their approach.
The characters would be in 3D and there would be a few surprising transformation of Mario.
The New Super Mario Bros. mini-games are already available in Super Mario 64 DS will comprise newer mini-games.
The launch of the game is expected next summer in Europe.
Via: JEUXFRANCE