What's even more remarkable is that at the time this was posted, the Wii did not have a significant user base advantage over the 360 (less than 1m consoles in America). And yet the Wii version still outsold the 360 version of Guitar Hero Aerosmith with ease... just as everyone who watches the typical sales pattern of these games predicted.
Guitar Hero World Tour Wii (2.56m) has nearly outsold the other two console versions combined (360 = 1.75m, PS3 = 1.04m). Nevertheless, no one seems to be arguing that Activision should drop support of Guitar Hero for the HD platforms because the Wii version sold more... you know, like we hear all the time about certain franchises (Call of Duty, cough cough). I find this interesting on a number of levels.
Although I generally don't like seeing threads necroed, I think it was appropriate here.
End of 2008 totals: Wii 42m, 360 24m, PS3 18.5m (made Jan. 4, 2008)
