ps3 active install base passes x360

[Grandia]

I wonder what they mean with active installed base. Either PS3 and Xbox 360 has in reality a much higher install base, the Xbox 360 has  actually 10 Millions more than they estimate here, the Wii also has real 11 Million more than here and the PS3 has 6 Million more. They undertracked all Konsoles heavy.