Microsoft Xbox 360 units sold, June 2008: 20m
Sony PS3 units sold, June 2008: ~14m
GTA IV, April 2008, 1-day and 5-day sales : 310m, 500m
Microsoft Xbox 360 units sold, February 2013: 76m
Sony PS3 units sold, February 2013: 77m
Black Ops 2, November 2012, 1-day and 5-day sales: $500m, n/a (Probably below 775m, MW3's 5-day numbers, as Activision withheld 5-day sales numbers for BO2)
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As you can see from those stats alone Black Ops 2 obviously wiped the floor with GTA IV's sales numbers but it's extremely important to look at the release date of both games. When comparing the total 360s and PS3s in circulation in April 2008 and Febuary 2013 you get a perspective of just how amazing GTA IV did sales wise. It's also important to note how CoD: Ghosts is not expected to do as well as Black Ops 2 by sales numbers not only because Black Ops 2 5-day sales apparently fell short of Modern Warfare 3's (hinting at a possible CoD decline), but also because of "a challenged global economy" and "the ongoing console transition", according to what Activision's own Publisher CEO Eric Hirshberg told investors at an investor meeting.
If you take how well GTA IV did with just 34m consoles in circulation by June 2008 (so a little less in late April 2008) and balance that number as if there were 153m consoles sold like in Feb. 2013 (so a little less in Nov. 2012) you'd be seeing numbers 5x higher. Obviously this doesn't mean GTA V will do 5x better than GTA IV sales but again, it puts things into perspective.
If there was ever a time to land a clean right hook on the Call of Duty Franchise, it's Q4 2013, and Rockstar Games is poised to do so this fall with the release of GTA V just 14 days before Q4 begins.
(i created an account because I find this all extremely fascinating)
