i can't find out why (in english, at least) the numbers are so disparate. wikipedia has a little bit of information:
http://en.wikipedia.org/wiki/Media_Create
do they really track 50-60%? because if there's no systematic error (regional bias, say, and there shouldn't be), 20% is outrageous. y-koron, any ideas? and what's this Dengeki tracking service?
Media Create is generally considered more accurate, but i have no clue what their tracking methodology is.
what does "track 50-60%" mean? do they actually get weekly sales data from say 2500 out of 5000 shops?
the Wii is an epidemic.