What's up with Mario Kart Wii sales?

[richardhutnik]

Ok, I check the worldwide list for sales figures.  I see how Street Fighter 4 is falling off.  I see that Killzone 2 is still in the top 10.  But then, right beneath it is Mario Kart Wii?  What the heck?  What is going on here? 

I am tempted to propose Wii games as bars that games sell over.

First, Wii Sports (top seller)

Then, Wii Play (top 3 seller)

Then, Wii Fit (top 5 seller)

Then, Mario Kart Wii (top 10 seller)

Anyhow, why does Mario Kart Wii remain where it is?