Added the November NPD sales data. 700k + copies seems a bit high to me. If we assume second month sales are as strong as first month sales (possible because the second month is December), we are looking at about 180k copies sold via retail in the US. If we take the rule that a game sells 2/3 of its copies in the first two months, we are looking at about 270k in the US for lifetime. Even assuming even-sales in Canada and Europe, that's 540k copies. I'd say 600k copies tops at this point.
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