As a Finn living in Japan, our preference for silence is certainly very compatible. I have never lived in one of those "small talk" cultures, which makes it hard to compare.

I do recall having a visitor (couchsurfer) over from US and having the bus driver get angry at us because we kept talking loudly in the crowded bus.

In Finland I feel like my signal-to-noise ratio is being judged. If I kept talking when I had nothing important to say, people might start taking me less seriously. I recall my dad commenting on someone "you should really listen to that person, when he speaks it is always something important".

Finnish IRC channels get pretty funny, as they often become idleness contests when no-one wants to break the silence with something insignificant.

I've noticed the "backchanneling" when speaking in Japan. I often need to make a conscious effort to keep saying "hai" periodically when talking, otherwise it may be assumed that I have either stopped listening or don't understand what the other person is saying.