It's mainly about some nice innovations from a company called Heat Geek, which developed a way to perfectly size a heatpump to a particular home (as many heatpump installers oversize their units to prevent customers from complaining of the cold), and figured out a way to use a much smaller water heat-exchanging water tank that can fit under a kitchen counter, which avoids needing some extra safety components that bigger tanks require, and eliminates the need to replace an existing good water tank, overall lowering the barrier of entry to a heatpump system quite a bit.

So basically just a nice boost to efficiency if their ideas are adopted by the industry, and lower cost of entry. I changed the title to be less vague and click-baity.