What should also be added, is that GTA:SA has low legs. If you look at this: http://vgchartz.com/swlaunch.php?reg1=America&game1=Mario+Party+8+-+Wii®2=Japan&game2=Mario+Party+8+-+Wii®3=All&game3=Grand+Theft+Auto%3A+San+Andreas+-+PS2&weeks=40
You see that after 10 weeks, GTA:SA was 3.7M ahead of MP8, 17 weeks later it is 3.4, meaning it has lost to a much lower selling game.
The same goes for Twilight Prciness, it was after 10 weeks 3.9M after GTA:SA while after 60 weeks it is 3.5M behind, meaning even a very low legged game (for being a Nintendo game) legged better than GTA:SA which means SMG (A mid-Nintendo game legged game) ought to legg much better than GTA:SA
http://www.vgchartz.com/games/userreviewdisp.php?id=261
That is VGChartz LONGEST review. And it's NOT Cute Kitten DS