Here is my theory for December NPD which covers five weeks:
Nintendo said a couple weeks ago that Wii sold over 3m in the USA in December...
We all assumed that was for a five week period, ala the NPD period. But...it may have been for four weeks (say Nov 30-Dec 27) as the press release was damn near the end of the fifth week. If that is the case, Wii had averaged ~800,000 in the USA through that four week period at least, and then it sold ~500,000-600,000 during the final week of the period. Otherwise, Nintendo would have just said "we sold over 4m Wiis in North America in the first four weeks of December". If that is the case then the figures Iwata gave would be consistent with NPD. I think this is possible - Iwata always mentions at Nintendo's briefings that NPD months are sometimes four weeks, sometimes five weeks. Maybe he forgets which is which sometimes?
People are difficult to govern because they have too much knowledge.
When there are more laws, there are more criminals.
- Lao Tzu
