While Just Dance's rise to the top of the charts has significant merit, these guys are making way to much out of it. A title with rising sales knocked a title with dwindling sales from the top spot. That's nice but hardly surprising.
The fact that it was a casual dance game instead of a core game or even NSMBW is surprising.
But the way this is reported you'd think Just Dance sold more copies than CoD:MW2 LTD not just for a mere week. If Just Dance can stay on top of the charts for weeks, then this will be warrented.