Nikon Reviews in a Nutshell

59% Of voters on NikonRumors wanted a 16 Mp. camera. Well, good luck to them.
Loosely quoting the late Steve Jobs: if you ask consumers what they want, you'll never get any real work done...
As a consolation, the D700 will stay part of the Nikon line-up – at least for a while – according to a Nikon France executive, so all these disgruntled potential buyers can still get a full-frame Nikon without the "excessive" resolution of the D800, at an agreeable 20% discount.
The D700 sells now for $2.200, down from $2.700, only days ago.

Notwithstanding, in 15,4 Mp. in DX mode the D800 is pretty close to these people's dreams, offers Full HD 1920x1080 30p video and a mayor general work-over at only a slight premium over the late D700.
Without even mentioning the rather exciting option to up resolution by a whopping 70%.
My bet is that, after the grumbling has died down, more people than not will prefer the D800 over its predecessor and end up shooting at 36 Mp. no matter what they say today.
How about that for a free upgrade that's only a button push away?

...

For the remaining 40 percent of us, Nikon has clearly upped the ante. A 36 Mp. sensor puts the D800 right up there with the $10.000 plus mid-formats, while the D800E – without AA filter – ought to be even more competitive as far as sharpness goes.
The latter is more likely to produce moiré and false color in very specific situations, but for studio, fashion and architecture shooters it is most definitely a valid option, especially considering its modest price ($3.300) in comparison with its medium-format peers.

The bottom end of the MF category starts at roughly $10.000 (Pentax 645D). With the discontinuation of Mamiya’s ZD, the only other integrated MF camera – the Leica S-System – comes currently in at $23.000. Without lenses, of course.
Digital MF backs cost much more. For example, the Phase One IQ 180 (80 Mp.) would set you back in the order of $50.000, without... BODY!

Even though some might argue that medium-format is an entirely different ball game, it is good to keep in mind that none of the current digital MF cameras comply with the 66 or even 645 standards of the film days. For now, the Phase One IQ 160 digital back comes closest, with a sensor size of 53.9x40.4 mm plus a heart-stopping price-tag. About $40.000.

The Pentax 645D, Phase One P40+ and Mamiya DM40 sensors all measure 33x44 mm (± 40 Mp. @ 6 mµ), which is a far cry from the 6x4,5 cm (± 75 Mp.) that at least the Pentax’s model name suggests, let alone 6x6 (± 100 Mp.).
With a resolution of 7.360 px. on the horizontal, the D800 in fact slightly exceeds the Pentax’s 7.260, however, the latter still wins on the vertical with roughly 10% more resolution (5.440 vs. 4.912 px.), which explains why its total resolution is slightly higher than the Nikon's (39,5 vs. 36,15 Mp.).

Nikon claims that this new CMOS sensor is up to par with the D700’s, which makes the 645D’s Kodak CCD look rather outdated, in spite of its larger pixel pitch of 6.1 mµ vs. the D800’s 4.9, at a virtually equal pixel density.
Even in the extremely unlikely case that the D800 were to be under par in comparison with the D700 as far as high ISO is concerned, with 6.400 standard ISO it still comfortably outscores the 645D’s extended 1.600 ISO by two full stops, without even considering the noise the Pentax’s old-fashioned sensor will most likely introduce at its maximum ISO setting.

However much I like the Pentax, DSLRs are in a different league. Weight, operability, automation, compatibility, performance, comodity and price are all elements to factor in at the moment to decide to invest in a camera system, and for the large mayority of users – including those craving MF performance – the D800(E) has a clear edge.
For example: even though Pentax 645, 66 and 67 lenses are far more affordable than the ones of their direct competitors, they are hard to come by, still rather limited in focal range and at least as or more expensive than their pro-level Nikkor peers, with exception of the super-tele Nikkors.

Nikon, on the other hand, offer lenses that are maybe not at the absolute top of the charts performance-wise, but do offer very respectable quality at a reasonable price.
A good example are the 50 and 85 mm Nikkors. Although the most demanding users will most likely shell out for the f/1.4 versions, the quality differences with their f/1.8 siblings are fairly marginal –  especially on FX – while the price differences substantial: $1.200 in the case of the 85mm f/1.4G vs. the f/1.8G or D, for example.

Still, the extreme resolution of the D800(E) presents challenges of its own, resulting – amongst others – in Nikon publishing a document with recommendations aimed at allowing users to take full advantage of the camera and not be disappointed with sub-par performance due to optically poor lenses or flawed camera management.
After all, there is only a limited number of users who have the pro-level knowledge and skills to manage a medium-format akin camera.
Even pros who come from flagship DSLR’s may need to cultivate some habitual MF but unusual DSLR habits to take full advantage of the extreme resolutions the D800/D800E are capable of.

Focusing for starters – the camera is very unforgiving in comparison with lower resolution models – but shake reduction and micro-vibration management as well.
What used to be sturdy supports for relatively lowres cameras in comparison, may now – al of a sudden – produce unsatisfying results, while lenses once considered outstanding may flagrantly expose their flaws with cameras that place such extreme demands on optics.
In an ideal world, one would want to mount MF lenses on the D800, however, the likelihood of Nikon making its own or – even less likely – third party mid-format lenses somehow compatible with this camera is null, even if it were technically feasible.

The following graph compares the D800 specs with the Pentax 645D’s. Depending on your application, some advantages of one or the other may be irrelevant but, overall, Nikon appears to present us – once again – with a paradigm shift worth pondering: a portable studio with certain MF-akin management demands or MF studio quality with operability and portability restrictions. Take your pick…

Here, the advantages from a DSLR user’s point of view are marked in red. A MF studio user’s priorities might be different – even though I doubt that...
The objective is to change the (IMVHO) rather limited perspective of potential D700 upgraders, and position this camera where I believe it ought to be: as a direct competitor for low-end Pentax, Phase One and Mamiya digital Mid-Formats at between 1/3 and 1/10th of their suggested retail price.
If pre-orders are any indication, it appears that Nikon are betting right...

See also:
DxOMark: Nikon D800E and D800 take the top slots in Sensor Ratings.
DPreview: Nikon D800 first impressions.
Nikon and Adobe add support for the D4, D800 and D800E.
Nikon Rumors: Nikon D800 issues.