A successor to the Nintendo Wii has been talked about for quite a long time, back to the days of Michael Pachter stating that the Wii HD was merely a formality. However, Nintendo of America has stated that they won't even start talking until Wii 2 until their goals have been met.
According to Nintendo of America president Reggie Fils-Aime, their current goal is for the Wii to sell 45 million units in the United States.
Speaking to Kotaku, he said "As we sit here today we're saying the Wii has many, many more units to sell. After we've reached an installed base of 45 million here in the US, we can have a conversation about the next generation."
This means that Nintendo's next console could still be a few years away.