Actually he talks about "popularity" however without knowing how many people are posting here from japan, this says nothing at all. Also as soon as you don't analyze the posts you don't know if it's popularity or not since you don't analyze the content. Maybe they talk about "I dislike something in Japan"? statistics only make sense when you have a bigger picture, everything else is just guessing how it could be and not how it is.
I think the post makes it pretty clear that it's about how popular stories about various countries are, it's not trying to establish a popularity ranking of the countries themselves.
