Not sure if you all caught this on the Fred Miranda site with the D800 and 5D MK3 comparison but I do like the proven workaround feature on the SNR portion of this article which states:
"I know this is disappointing for Canon shooters but on the bright side, there is a workaround if you shoot RAW. Start by overexposing (up to 1 stop) above the correct exposure before taking your shot and then normalize the exposure later in software. This gives you the correct exposure but the shadow detail is much cleaner, just in case you need to push it a stop or two. Alternatively you could use ISO L (50) for low contrast situations whenever lighting and wind conditions allow. However, make sure that there is no clipping in the highlights (blinkies) because essentially when you are using ISO 50, you are already compromising highlight detail by about one stop. I've used this workaround for many years and have been happy with the results."
Link:
http://www.fredmiranda.com/5DIII-D800/index_controlled-tests.html
I typically don't pixel peep or crop / zoom at this level and merely take the photo as it is - so this stuff doesn't bother me as much. These zooms are pretty extreme in the examples and at storing 36M images vs. 22MB and sacrificing on the higher ISO side, I'll still take the 5D MK 3 - should be here within a few hours. I can live with this!