I am surprised at all the positive reviews...I recently bought a d700 and a d600 to see which would best replace one of my d300s which has nearly 200,000 clicks. My first impression of the d600 was favorable but upon closer examination the images had an unnatural look to them...overly saturated and with cartoony contrast...I found that this was difficult to correct in post or with in camera adjustments. I was very impressed with the look of the images at high ISO but to me the overall 'look' is the most important aspect of a camera and this was a deal breaker. I could have gotten over the plasticky feel and tiny grip...a battery grip would have probably improved the ergonomics. I could have gotten over the extremely small autofocus array. I could have gotten over the viewfinder design which cut of the corners of the frame...together though I found this camera unacceptable.
The d700 on the other hand felt solid and well built [as would be expected from a higher end camera]...The viewfinder was a welcome improvement from my dx cameras...it is huge, bright, and clear...the ergonomics were similar/the same as my d300s's. None of this was a surprise...what was a surprise was how much nicer the files looked from the d700. The raw files had a much more natural look, better color rendition, better white balance in auto, more realistic contrast etc. Even more surprising was the low light performance compared to the d600. While the d600 has less grain in general I found the d700's grain to be more easily eliminated in post and also I felt like the detail was more well preserved as well...Images were fairly sharp albeit quite grainy even at hi 1.
Of course this test was not scientific and I am not a pro camera reviewer. I am simply someone who makes a living with his cameras and knows what he likes. The megapixels weren't an issue since i need to downsize my frames to 3k pixels on the long end before they can be syndicated. So yea I'll be keeping the d700 and waiting for a d400 for when I need the reach. Considering the d700 is going for 1999.96 refurbished I would say it is a steal compared to the more expensive and toyish d600.