flagship on 11 July 2008
I think one other possibility for numerical changes is shipped units, if you found out that retailers were selling about 75% of the copies they received the first week and you estimated first week sales at 160K but later learned that the initial shipment to retailers was 250K you might want to correct your data for that.
This is especially true for things like the Wii or WiiFit in the first couple weeks where you have near 100% sell through, just finding out shipped units (which is sometimes even published in news articles) basically gives sell through figures.
