That's a lot better than I expected. I was expecting it to be the worst selling mainline dual-version Pokemon game in Japan by a fair margin (so, less than Fire Red/Leaf Green at 3.15 million), but it has a fairly good chance of beating that. If it keeps the same first week to lifetime ratio as Black and White did, it'll make around 3.4 million. I wouldn't put that past BW2, but it depends on how many 3DS buyers buy it mostly.
Still, 3-3.5 million seems like a plausible result. Which, while not bad, isn't exactly brilliant by Pokemon standards. Had it been a 3DS Pokemon (and not a sequel), it would most likely have been looking at somewhere between Ruby and Diamond/Peal (5-6 million). Still, a new 3DS Pokemon could still do near those levels.
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