How long until we hear about people who switched to Nikon wanting to switch back to Canon.....
Did somebody just call my name?
No seriously, I'd say it'll take a while. For me, and I think for many other people, the Sony sensor got Nikon attention, but actually Canons recent price policy had me buy the D800 instead of the 5D3.
The 5D3, good as it is, is priced at the top end of what they could take. So is the Speedlite 600XT, the 24-70 L II (gee, look what Tamron gets you for half the price), the 1D-C and, most recently, the 6D. DPReview put it very nicely: "Whereas Nikon seems to have taken the approach of taking away as little as possible from D800 when creating the D600, Canon appears almost to have gone the other way, removing as much as it thinks it can get away with at the price."
- I'm not saying Canon is stupid to do so, and I'm definitely not a Nikon fanboy, but this is a big part of what had me switch to Nikon, and since I don't see that changing soon, my bet is that system switchers like me will not reconsider as quickly.
For the big MP body: I don't know why you wouldn't want it, all Canon has to make sure is to include various downsized RAW outputs (and yes I find it annoying that Nikon didn't have that idea for the D800). They might need a pretty fast CPU in the camera, but in principle that shouldn't be a problem. Offer RAW output @46, 23 and 11.5 MP and no one can say it has too many MP. Hardly anyone NEEDS 46MP, but having it in the bag for landscapes or some commercial shoots is definitely a selling point.
However, not only the resolution, but also the aim to go for higher DR sounds like they're back on track with their sensor development. Someone here mentioned some special technology in the Sony sensors, could you go into more detail on that? I think it is very apparent that Sony has got some magic going on for the shadow noise/ DR. It's ridiculous how those Sony sensors can save your day after you screw things up in manual mode, so Ive been wondering why Canon and Nikon sensors can't put up with that. (ok this was already answered while I was typing)