http://www.1up.com/do/newsStory?cId=3162770
The FT numbers come from NPD, GfK and Enterbrain. I have very quickly calculated the VGChartz numbers for the same time frame and markets. Please feel free to correct any mistakes.
FT VGChartz
Wii: 9.0 9.1
360: 8.9 9.1
PS3: 3.7 3.7
VGChartz appears to be very acurate for all 3 consoles.