Good point Stof. If you look at attachment rate. It is as following.
SMG: Total sales after 11 weeks: 5.15M. Userbase: 20M = 25.75 % attachment rate.
Assassins creed Ps3: Total sales after 11 weeks: 2.05M. Userbase: 9.4M = 21.8 %
Assassin's Creed X360: Total sales after 11 weeks: 3.25M. Userbase: 16.5M = 19.6 %
SMG has highest attachment rate and is likely to have most legs.
Now, off topic (I just do this for myself, you don't have to read this)
SMG attachment rate: 11 weeks = 25.75 %
CoD 4 X360: 11 weeks: 4.3M. Base: 16.5 M = 26.0 %
CoD 4 Ps3: 11 weeks: 2.1M. Base: 9.4M = 22.3 %
CoD overall has a lower attachment rate than Wii, but X360 version is higher.
http://www.vgchartz.com/games/userreviewdisp.php?id=261
That is VGChartz LONGEST review. And it's NOT Cute Kitten DS