The reason DS sold so much is because it launched at 149$/euros.
Both the 3DS and PSP2 will be way more expensive, 3DS will have the same launch price as PSP1, PSP2 will be even more expensive.
I think the PSP1 lifetime sales will be around 75-77 million, maybe 80 million, depends on pricecuts and when NGP will release and how much million it will sell after NGP releases.
NGP will do around 90, 3DS around 100-110 million.









