The Dutch are AKA "The Koreans of the West" (in the context of Go), because that little country has such a relatively high number of Go players per x inhabitants.
But if you look at how "serious" those Go players are, how much time, money & effort they spend on the game, I am quite convinced that in fact it's Poland that deserves that title more.
Judging from how many Polish customers I have compared to Dutch, and especially seen the discrepancy in disposable income, adjusted for the size of the populations, Poland takes the lead in "Go seriousness", as far as Moyo Go is concerned. Moyo Go Studio is not "cheap", but it is indispensable if you want to do thorough Go pattern research (Statistical Move Likelihood etc.)
Hardly a week goes by, or I get another Polish customer. I won't disappoint them - I'm working on something cool*, as usual :)
* Won't take forever to roll out, either.