Heat pump technology is certainly out of the "early adopters" phase. It is basically the standard for new buildings in Europe (at least Northern Europe, I'm not sure about the South), and has been for years.
In Germany, where I currently live, they recently passed a law that constrains what kind of heating system you're allowed to put into your house to a point where basically only a heat pump fulfills all criteria (perhaps with the exception of pellet heaters).
In Germany, where I currently live, they recently passed a law that constrains what kind of heating system you're allowed to put into your house to a point where basically only a heat pump fulfills all criteria (perhaps with the exception of pellet heaters).