One of the reasons why Sony was doing better than Nintendo some years ago was because they created a new market, Sony’s PS and PS2 and their games where aimed to entertain not only kids and youngsters but also young people from 20 until 30 years old. Nintendo focused on entertainment only for kids during some years, but with the DS and the Wii hey have created a new world, a new market. Now even 50 years old people are playing video games! And not only men but also women.
Look at the next charts, you can see the balance between men and women in Nintendo DS chart. Blue are men DS owners, pink are women, the x-axis represents age and Y the quantity of machines.
People with DS in Tokyo and Osaka. There are more 44 years old people with DS than 17 years old with DS! Isn’t it amazing?
Just to compare, look at the same data but for the old Game Boy Advance.
These charts are from japan.cnet.com. If you want more charts this is the one for the Wii and this one for the Game Cube where masculine predominance is obvious.