The D800 broke many barriers when it was released - at the time of release/review DxO Mark awarded it the highest score in it's history (indepth analysis here); Mike Johnston at TOP made the following glowing statement following his own personal review:
For 25 years I've deliberately made it a point to experience a wide variety of cameras of most types: I've tested dozens of cameras, owned dozens of cameras, and seen and handled literally hundreds more.High praise indeed although it hasn't been all positive news.
[..]
Cutting to the chase: all things considered, the Nikon D800E and Nikkor AF-S 35mm ƒ/1.4G lens is the best overall photographic device of any description I have used thus far in my life.