Theres also an important question on multiple console ownership, and console replacements due to system failure.
Since the PS2 was also a DVD player, I know of a lot of people who used the console as both a console for the kids and a DVD player for their movies, I suspect that we have that phenomenom going on today. So I suspect a reasonable proportion of those households would have bought not one but perhaps 2 or 3 PS2s.
On the other hand the Wii is reliable to a fault. Its best experiences are shared as a group and theres no convenient DVD player so my suspicion is that it can reach a greater proportion of houses than the PS2 ever did even if the sales figures don't indicate this.
Do you know what its like to live on the far side of Uranus?
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