From everything that I have read, this is correct. Russian Orthodoxy is different than Serb Orthodoxy which is different from Greek Orthodoxy. My suspicion is that they hold to the fundamentals but they vary in cultural areas.
That would make one wonder why America Orthodoxy would be different from any other type of Orthodoxy? They are simply following cultural trends of the nation. Perhaps I'm missing something.
In those countries the predominant religion is Orthodoxy. The individual cultures were built around Orthodox faith, incorporating it into the way of life, not the other way around as is the case in America.
Trying to fit a culture into Orthodoxy doesn't change Orthodoxy; it only gives it ethnic "flavor." Trying to fit Orthodoxy into a protestant/secular culture does.