Two new Pokémon™ games, Pokémon Black Version and Pokémon White Version, for the Nintendo DS™ family of systems will be released in North America in spring 2011. Introducing a new storyline and the next generation of Pokémon, the new releases will feature the Legendary Pokémon Reshiram™ (Pokémon Black Version) and Zekrom™ (Pokémon White Version) on the game covers worldwide.
“Pokémon is a true worldwide franchise with legions of fans in every corner of the globe,” said Cammie Dunaway, Nintendo of America’s executive vice president of Sales & Marketing. “We know these fans will be thrilled to discover this new generation of Pokémon next year.”
The launch of Pokémon Black Version and Pokémon White Version follows the incredible consumer response to Pokémon HeartGold Version and Pokémon SoulSilver Version, which have sold more than 8.4 million units combined worldwide to date. The Pokémon video game series has sold more than 200 million units worldwide since it was first introduced 14 years ago.
Notice that it says "for the Nintendo DS family of systems", so I guess this isn't a 3DS exclusive- or the games are going to be back-compat with all DS' in a non-3D format. Seems like a safe bet anyway since we already know that the 3DS 3D can be switched off if you like.