You're missing the point.
The Xbox 360 has had a significant advantage time-wise over both the PS3 and the Wii. Nintendo, in about 10 months, has caught the 360 which has been on the market a full year longer.
Not only that, but just do a comparison at your local store. When was the last time you saw a Wii sitting on a shelf anywhere? Sales of the Wii show no signs of letting up any time soon.
So in short, Nintendo is murdering their competition.