Well if NPD don't track Amazon theres this -> http://news.punchjump.com/article.php?id=10243
"Monster Hunter Tri, released Apr. 20, ranked No. 11 in Apr. U.S. retail data by NPD Group Inc., moving between 108,000 and 143,000 units in the first 10 days of sale."
The numbers are so vague. So 35k discrepency? It could have have been top ten, according to NPD?
“When we make some new announcement and if there is no positive initial reaction from the market, I try to think of it as a good sign because that can be interpreted as people reacting to something groundbreaking. ...if the employees were always minding themselves to do whatever the market is requiring at any moment, and if they were always focusing on something we can sell right now for the short term, it would be very limiting. We are trying to think outside the box.” - Satoru Iwata - This is why corporate multinationals will never truly understand, or risk doing, what Nintendo does.