Nintendo’s portable consoles have over the years received three sets of Pokemon Mystery Dungeon games, Pokemon Mystery Dungeon Red and Blue Rescue Team on the Gameboy Advance and Nintendo DS in 2005, Pokemone Mystery Dungeon: Explorers of Time and Explorers of Darkness in 2007 for the Nintendo DS and Pokemon Mystery Dungeon: Explorers of Sky in 2009 also for the Nintendo DS.
The latest installment in the series is set to hit the Nintendo 3DS in two installments slated for later this year in Japan – Pokemon Mystery Dungeon: Magnagate and Pokemon Mystery Dungeon: Infinite Labyrinth. As with all other previous releases, the game will be developed by (now) Spike Chunsoft.
The above trailer will provide you with a look at the game and its improvements / additions. There is currently no confirmed release date outside of Japan, but I would say chances for an eventual release during 2013 are strong.