About the Canon alternative: the Canon 6D, on second sight, is indeed a much better deal than it looks like on the first sight.
Yes you only get 11 point AF, but the middle point is extra sensitive (-3 EV) AND ironically these mere 11 AF points are MUCH better distributed than the 39 AF points of the Nikon D600. So actually I would prefer the 6D AF over the D600 AF, even if its technically inferior. But it is more practical.
Yes you get a lesser noise performance, and better dynamic range etc. BUT Canon included stronger and apparently pretty good noise reduction algorithms (I've seen multiple YouTube videos and website articles of clueless noobs who claim the ISO performance of the 6D would be better. Even DigitalRev claimed that) AND the camera allows you to go to ISO 102,400 while the D600 for some odd reason only allows ISO 25,600 at Maximum, despite being pretty noise free even at this maximum.
So yeah, bravo Canon, you created a pretty fierce competition for the D600.
There are details I dislike, though. No second memory card slot for making a backup of your picture. On/Off switch not right next to the release button.
And there are features of the D600 I find most highly appealing, like the silent shutter.
Ultimately, my ideal camera would be a D600 with a more reasonable distribution of AF points. And I really would like to have a flipscreen on it, too.
Then I could live with the little faults the OP mentioned, like no change of aperture when using Lifeview. Yeah, annoying, but not dealbreaker. Also I would put up with the other faults of the camera, like often oil spots on the sensor for the first 3k acutation, or lack of 1/8000 sec shutter speed despite the fact the successor in spirit (D7000) has that. The silent shutter and the fantastic sensor makes all that worthwile.
My Sony has a tilt screen and even moves around. Never use it.
I use my 5100 flip screen all the time. Really anytime I want to have an unusual perspective.
As for not being able to see in bright sun, I suspect that's more LCDs displays in general ... for various degrees of bright.
Since its so fun to quote Ken Rockwell, for after you quote him nobody wants to take you serious anymore, here goes:
Nikon vs Canon:
LCD Quality
As of 2012, Nikon's four new full-frame DSLRs (D600, D800, D800E and D4) share a problem new to DSLRs: they tend to be a bit too yellow when new! We have to depend on the accuracy of our LCDs, and Nikon has taken a step back in 2012.
Another subtle but important advantage of Canon is that their LCDs have the same 3:2 aspect ratio as their images, so the images fill the entire LCD. Nikons use a different aspect ratio for their LCDs, so while two cameras may have the same diagonal size rating for the LCD, the actual image size is bigger on the Canon DSLRs! Another reason as of 2012 I've switched to Canon.
Canon's LCDs are usually behind anti-reflection coated glass or plastic, so we can see bright, contrasty images with great blacks while outdoors, while Nikons usually use uncoated screens on which we see reflections of the world around us. On Nikons therefore, it's much more difficult to see our images in daylight.
Canon's screens are often coated with magic stuff that resists grease and smudges. Nikons are not.
The Nikon D90 with onyl 12 megapixels beats the D600 at ISO 1600 in both less noise and more sharpness if you compare images.
Err, sorry, but thats an older APS-C sensor vs a brand new FF sensor. Even the D600 24 Megapixel pixel size is still (a little) larger than the D90 12 Megapixel pixel size. The DxOMark rating differences between these two is also extreme.
So unless you want to claim that Nikon actually LOST knowhow between the construction of the D90 in 2008 and the construction of the D600 in 2012, I would say its pretty safe to say you're wrong.
Unfortunately noise is a highly complex issue. With the right program and optimizing noise reduction by hand, one can get really impressive results. I've seen example images at ISO 25,600 out of a µ4/3" camera that had no visible noise at all. Doesnt mean that images from such a camera WITHOUT noise reduction will not have a lot of noise in them.
