Sony just unveiled three new digital cameras that feature some interesting advancements. These advancements will surely drive digital cameras into the next era.
The RX100 IV and the RX10 II both feature 1" backlit CMOS sensors that are stacked. These sensors are not stacked in the sense of a Foveon sensor with layers dedicated to different color channels. Instead, Sony has stacked the light sensors and the circuitry. This allows the sensors to have increased light sensitivity, use less energy, operate quicker and take up less space. I doubt that any of these are major improvements, but a bunch of small improvements do add up.
My prediction is that this new technology will sweep through the small sensor market. I think in the next year or two you'll begin seeing Sony's stacked sensors show up in a bunch of cell phones. I think eventually all of Sony's sensors will be stacked.
The a7R II has a 42 megapixel backlit full frame CMOS sensor, which is the first full-frame CMOS sensor that is back-illuminated. That allows Sony to increase the resolution without compromising high ISO capabilities.
This camera will surely sell well. Those considering the Nikon D810 will take a long look at the a7R II. Those considering a digital medium-format camera will take a long look at the a7R II, as well. All of that resolution will be quite tempting for those who are constantly after the latest and greatest (a trivial pursuit, but a common pursuit).
Sony is the world's #1 camera sensor manufacturer. They are also one of the top digital camera manufacturers. These new advancements will surely ensure that they remain at the top.