It's been a bit over a year since the catastrophic earthquake and following tsunami in the Sendai area of Japan. It's been several months since the devastating floods in Thailand. Those threw the modern world of manufacturing into chaos. Should I have said "utter chaos"? Writing idioms are plentiful elsewhere, wouldn't you say?
New cameras have been arriving in a trickle. Nikon has brought a lot of the excitement lately with the D800/D800E and the D4. I'm waiting to see the D400. No, I'm not a Nikon fan so perhaps, a bit of history will help. I chose an Olympus E-1 over the D70 or D100. At that time, there wasn't much comparison. Even with the smaller sensor, the E-1 had better image quality. Another factor was that you couldn't pair it with cheap, rubbish or old lenses. It was all digital and required new lenses, all of which had outstanding quality. Given the cost of equivalent lenses, Nikon would have cost me about twice as much.
Fast forward (okay, a writing idiom) to 2007 and the Olympus E-1 successor had finally arrived. So had the Nikon D300. The Olympus E-3 looked somewhat less than adequate against the D300. Mind you, the auto focus was not pathetic, finally. 11 cross-point auto focus sensors were brilliant. Contrast that to the D300's on-again-off-again-are-we-in-the-correct-situation 51 AF sensors and people see the sheer number of sensors and forget the rest. The D300's 51 AF sensors aren't always all in use and the remaining number is much more humble. Still, it's quite amazing as a system, but overly complicated. The Olympus AF works its best with certain lenses marked "SWD" for SuperSonic Wave Drive, of which the 12-60mm was represented as the fastest AF in combination with the E-3.
The E-3 had one truly pathetic downfall--the anti-aliasing filter was too strong and the images were not very sharp, even in studio lighting. Sure, it had a 10 MP sensor, but you could get great images from the E-1, being careful about the 5.1 MP size. You just couldn't fix the anti-aliasing filter of the E-3, no matter what. Cue the funeral march.
In 2010, Olympus introduced the E-5. It fixed the critical issue with the E-3, brought a higher resolution LCD, kept the brilliant AF system, used a dual-core CPU and 12 MP sensor, and made Four-Thirds shooting good again. It still used the poor ergonomics of the E-3 but so what? Set things ahead of time and plan around the problems. I made the jump in November 2011.
I want to say that I'm incredibly pleased but there is an underlying noise from ISO 400 up and I'm not comfortable with ISO 1600 images at all. Looking at some images from a D300, they're no better at ISO 2500. It wouldn't have helped to jump ship.
So, where is the D400? Given that the D7000 is arguably better than the D90, I'm wondering how much better the D400 will be. The exposure metering system will have been improved, probably with double (or more) sensors. I doubt the AF system will have been improved, except for tweaks. (I don't use AF, by the way, but it's important to many people, especially the professionals who keep everything on automatic.) Of course, the big change will be the image sensor. Will it be the 16.x MP sensor from the D7000 or something newer but equal in number? I suspect Sony will supply a slightly enhanced version for the D400 and it will also go into the D7000's successor. I still haven't heard any rumor about the D400, except that it's delayed until the D4 and D800/D800E bodies can be put to full capacity in the factories.
Considering Olympus' new OM-D series, I'm wondering if many people will jump ship the other way and take advantage of some good fixed focal length (prime) lenses. The E-M5 was just given What Digital Camera's Gold Award in their review of the camera and that says a lot to me. Now the final total was 90 % which puts it dead even with the E-3 and three points behind the E-1. Considering how mirror-less system cameras were doing poorly at the beginning, I'm shocked.
It's a matter of time until dSLRs become a thing of the past. I suspect they'll be there in medium format for a while but for handheld jobs, smaller and lighter are better. Olympus showed the world that back in the 1970s with the OM-system and Nikon complied with demand and went smaller. I can't wait until all brands announce smaller systems with exceptional image quality. I know that the Nikon D400 won't be smaller, but I'd like to see it, just the same.
Update 2012.11.11: Still waiting, and with the D600 out, plus the D5200, everyone is wondering, I'm sure.
Update 2013.10.08: The D610 has been announced. It's likely a matter of manufacturing capacity and anticipated demand. I suspect that Nikon feel that the "full frame" fanatics who would have bought the D400 have gone to the D600 already, the majority of the remainder might have gone to the D800, and the remainder are complaining that there is no D400 yet.
Given that Ricoh/Pentax have announced the Pentax K-3, I think the wait is over for those who wanted to switch because of the D400. This new body has an amazing array of technology and seems quite capable of going where the D7100 has not--sports, what I photograph.
Update 2015.11.29: Holy shhhhh! In the last few months, there have been rumors about the D400 again, especially since the Canon 7D Mk II was put on sale.
Back in April, the D7200 was introduced to supplant the D7100 and D300s. I have one and it's good, but whether it could replace the D300 in all ways, I'm not sure. The body isn't nearly as strong.