It's interesting how the latest technology in photography often seems to first appear first in the lower grade cameras. The first mass-produced autofocus camera was the Konica C35 AF, a simple point and shoot model released in 1977. Now all cameras have an autofocus feature, even MFDBs, don't they?
The latest feature in P&S cameras is the 'back-illuminated' sensor which allows for an increase in the amount of light each sensel is able to collect because the interconnects, and other electronics in the case of a CMOS sensor, are on the other side of the sensor.
A future back-illuminated Nikon D3s might increase high-ISO performance by yet another stop.
However, the ultimate limit to such increases in performance is photonic shot noise, the random arrival of individual photons which is part of the fabric of quantum reality.
The smaller the sensor, and the smaller the pixel, the more significant shot noise becomes.