Nintendo has, as part of their earnings release today, updated data for investor relations, indicating the sales units of their games, per console. Of interest is the Nintendo 3DS data, indicating the sales of Pokémon X and Pokémon Y, as well as Pokémon Omega Ruby and Pokémon Alpha Sapphire.
Selling at 14.46 million units worldwide, Pokémon X and Y are the top-selling Nintendo-published 3DS titles. Keep in mind that these games were released on October 8, 2013.
Pokémon Omega Ruby and Alpha Sapphire, being released on November 21, 2014, are the third top-selling 3DS titles, selling at 11.46 million units.