The D800 announcement (see below) is causing some misconceptions to be espoused, so let's cut that off before it becomes Internet Truth:
- 36mp makes the D800 a Medium Format camera. No, it doesn't. It means it has about as many pixels as some older and lower cost MF digital backs, but it doesn't elevate a D800 to "medium format." For the same reasons that we used MF in film, some continue to do so in digital: less magnification for same print size, differences in lenses for larger versus smaller formats, plus a new one in the digital age, more true bits of data per sampling point.
- The D800E should be cheaper because it removes something. No, it replaces something. What happens in the AA/IR filter, microlenses, and Bayer filtration is a very complex optical dance. You cant remove the AA filter and expect it to work--the focal plane would have moved and the optical paths trying to make light telecentric would have changed. The D800E has a different filter than the D800, one without an anti-aliasing component. As to why it is more expensive, that's going to be an embarrassment to Nikon, I think: they predicted they'd make far fewer D800E's than D800's, thus it would cost them more (both in parts and in all the things associated with an item sold in lower quantities, e.g. inventory costs). I predict they'll be wrong. Completely wrong. Of course, Nikon gets the last word here, because they can't make more D800E's than they order parts for ;~). That leads me to a prediction: the D800E will be a constant sell-out.
- You won't see any resolution improvement because lenses aren't good enough. Wrong. You'll see improvement, the question is how much and what you'll see. Let's just pretend for a moment that all lenses are perfect in the central area. More pixels will mean that the central area stays nice and truly resolves what the increase in pixels implies, but the corners will look worse, ironically because the sensor is resolving how much worse the corner is than the center. But even with the visually worse-looking corners, you're probably still resolving more.
- Corollary: you need lenses that resolve 100 line pair per millimeter on the D800. From one standpoint, yes, you do. If you want to obtain all the gain that moving from 24mp (D3x) to 36mp (D800) implies, you'd need lenses that resolve somewhere near 100lppmm versus 80lppmm. This is one of the reasons why I wrote previously that we're entering into the realm of declining returns. Going from 3mp to 12mp was a big, dramatic change, and no other component started to hold back the gain from the sensor itself. Going from 12mp to 24mp was reasonably big, and again no other component really hurt you much, though some lower-end lenses definitely showed their shortcomings. Going from 24mp to 36mp is not so big, and now we do have other issues starting to keep us from getting all the gain we expect, with lenses being potentially one of them.
- Not much new over the D700. Untrue. The skin may be (mostly) the same, but underneath virtually everything is new. For the most part, it's a D4 with a different sensor in a different body. If they had just stuck the same 12mp sensor into the D800 I'd still call it a substantial upgrade from the D700.
- You can't buy an AA filter for the front of the lens. It's been a long time since I looked, but last time I did, yes, you could. But it's very expensive, hard to find, and doesn't quite produce the same results as having the AA at the sensor.