I feel it's a fully valid prediction, given that the other three generations of Pokemon (Red/Blue, Gold/Silver, Ruby/Sapphire) reached 31m, 23m, and 15m respectively. (I'm discounting Fire Red/Leaf Green as they're effectively remakes of the originals and thus not their own generation.) The current estimate may be a tad high, I'd admit, but I still feel some strength to this stock, especially with so many improvements being made to the games themselves. This pair is very close to Ruby/Sapphire in Japan after only 3 months, so I suspect it will perform better than that duo and in line with or better than the current price.
Citing VGChartz and the wired.com article from Feb. 1 on this.
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Citing VGChartz and the wired.com article from Feb. 1 on this.