From http://www.imaging-resource.com/PRODS/D30/D30A4.HTM, "The Active Pixel CMOS image sensors used in digital imaging are very similar to a CCD sensor, but with one major difference — supporting circuitry is actually located alongside each light receptor, allowing noise at each pixel to be canceled out at the site."
Somewhat true, but I do see the connection with the on-sensor heat production mentioned in your previous post. And that IR quote is wrong in one major way: the noise cancellation done at the pixel level in CMOS sensors is eliminating a type of noise that CCD's do not have in the first place, so this is a matter of overcoming a weakness of earlier, rather noisy, CMOS sensors, not an advantage over CCDs. The CMOS high ISO speed noise advantage has a different basis.
At normal exposure times (under 1s, say), the main noise source that sensor and amplifier design can do much about is amplifier noise, not heat or any other source of noise within the photosites themselves. CMOS sensors do the initial amplification very early, and massively in parallel, as amplification is done in each column of pixels: thousands of amplifiers in total. With CCD sensors, the amplification happens off the sensor chip itself, using just a few amplifiers which therefore have to operate at a far higher rate. The far lower operating frequency of the on-chip amplifiers of CMOS sensors help to lower amp. noise. (However, the tiny on-chip amplifiers of CMOS sensors might have a lower maximum DR than the far bigger off-chip ones that can be used with good CCD's, and this might relate to why at minimum ISO speed, high end CCD's have higher measured DR.)
On the subject of amplifier operating frequency and noise, Dalsa spec. sheets describe how noise level can be decreased and DR increased by lowering the read-out rate. Also, one often stated reason for increasing the amplifier count with CCD's, is to lower the operating frequency needed by each amplifier, and so reduce its noise.
(Aside: Dalsa builds amplifiers in at each corner of its FF CCD sensor units, and maybe Kodak does too. The dark noise level and DR figures in their spec. sheets are for the signal coming out of the amplifiers, so includes amp. noise.)
