87% of Wii owners in Japan play on the main screen in the house

"Bring the family back together in the living room is Nintendo’s approach for the future. As Nintendo researchers found out 87% of Wii users use it on the biggest screen in the house, which is still the one in the living room. With the introduction of new game types like Wii fit and Wii sports, as much as the Nintendo DS, Nintento could expand the gaming population worldwide. Both devices are used by both sex and by a wide range of age groups. In average more family members use the the same Wii as other consoles are shared. Now Nintendo tries to widen up the variety of things you can do with a single gaming device by establishing one machine that satisfies all kinds of users in all possible ways."
Source: CyberMedia blog, 11th May 2009