I have looked at the charts and it seems that the Wii is doing better than the PS2 in its first two years. Only in Japan does the Wii not do better than the Ps2 did, everywhere else it does. If the wii stays on this pace then there is no doubt that the Wii will surpass it.
From the looks of the trends, I see no reason why the Wii would stop selling as well as it has. Supply should start increasing a bit more for 2009 and the Wii will get some third party support next year. This tells me that the Wii will most likely sell better these next coming years then it already has.
The wii still has a good 3-5 years before next generation gets underway. Also it will not drop off the face of the earth when Wii 2 comes out. This is an absurd notion. I see no reason to believe that the Wii won't sell 150-170 million units in its lifetime.
The only arguement against the Wii is that the competitors are much better this generation than those of the PS2, which could potentially take away sales.
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