He said ABOUT 10 million copies.
It's still a popular game so it needs a lot of shelf stock.
Having said that it's still a difference, if we assume the about means more like 9.7 or something, then VGC is 2.5 million down.
Then again think about it.... You go into a games store, how many consoles do they have on average for say, X360? And how many copies of Mario and Sonic do they have?
VGC generally seems to show shelf stock of 360 at about 1 million (most will be in America, hardly any in Japan)
2.5 million stock for something like M&S doesn't seem too excessive.
Breaking the same thing down regionally.
In Japan there are probably fewer than 50k X360s in stock at any one time, probably even less than 20k
Wii stock of M&S in Japan will probably be higher than 360 stock... it sells about the same each week but games are usually more stocked than consoles even if they do sell similar.
DS stock of M&S in Japan must be much bigger, it sells 4-5 times as much as the Wii verson
Total M&S in Japan is probably 200-300k+ (mostly DS)
In America the two games combined sell about the same as the X360 each week, but again games are likely to be stocked better, so while X360 stock might hover around 400-500k in the area, the games together will probably be a good 100-200k higher than that.
In PAL regions all three things sell more each week, but I find it hard to judge whether the split nature of the market would need more or less stock than the Americas, but as everything is selling more, I'd guess an extra 100k on top of each compared to Ameirica.
Total those up and you get 920k-1150k for X360
1400k-1900k+ for M&S
Games like Mario and Sonic need a lot of stock constantly.
Games like GTA/MGS need huge first and 2nd shipments, and maybe some smaller ones after that, but generlaly they just slowly dwindle their stock down as they get older, unlike M&S which needs weekly/bi-weekly replenishment