I've updated my database pages with the D7100 information.
Now that we Westerners have all gotten a chance to get some real sleep while contemplating the D7100, here's what I have to say:
It's almost exactly what I expected a D7100 to be: upgraded sensor and a push up the AF system chain, with a few new twists sprinkled in. As the name indicates, this is definitely an iterative step, and one that fits almost perfectly within the Nikon DSLR-upgrade modus operandi. No surprises here. Moreover, Nikon continues to not break things that aren't broken. That's far better than the alternative.
The corollary to the above is that I believe Nikon left themselves room for a D300s update, and I don't see any reason why they shouldn't do one. Indeed, the In Box messages from D300 shooters this week indicates to me that there may be even more dedicated pro DX users out there than I had originally thought, and I had already thought there were quite a few. I'll have my latest thoughts about a D300s followup, especially considering the D7100 details, sometime next week.
The 1.3x crop option is probably the most interesting aspect of the new camera. First, it nets you 7 fps. Second, it pushes the focus system across most of the frame you're going to record. Third, you still have a 15.3mp camera. This feature is going to please some wildlife and sports folks, even with the restrictive buffer.
It's hard to imagine where the consumer DX DSLR lineup goes next. More pixels means we're pushing the kit lenses into diffraction, so the immediate visible gain from more pixels is far less than we're used to so far with DSLRs. Not a big payoff there. We've also hit the pro parts' final migration down into the consumer lineup: there isn't a better AF system than the 51-point one being used in the D7100 in Nikon's parts bin, for example. Put another way, Nikon has pushed most of the pro technology from the D3/D4 into the D7100. To go further in performance parameters requires Nikon to break new ground. Will they do that on a consumer camera before pro? My guess is no. The D5 would have originally been scheduled for 2015, and if Nikon can stick to that and has some real technologies that move the pro body forward, then it only takes a year delay on a D7100 update to let some of that trickle down. But again, what that might be is unknown at this point.
I'm amused that all of Nikon's sample and marketing images were taken with FX lenses. Even Nikon might now get the fact that they need some real pro DX glass ;~). As usual, the samples are underwhelming and don't really show off what 24mp DX should be able to do. Not even close, actually. It's impressive that Nakano-san can handle a 500mm f/4 lens in air-to-air shooting like that, but it was too much lens for the assignment, IMHO. Should have been the 200-400mm, as the example used in the brochure looks like he accidentally set 1.3x crop but composed for full frame.
At US$1200, the D7100 is a lot of camera. If you consider the D70 -> D80 -> D90 -> D7000 -> D7100 progression, at that basic price point we've seen an amazing push forward in capability and performance in nine years. Yet at each individual step (every two to three years) the difference hasn't been quite so dramatic. Which brings me to this: at US$300 less than the D7100 we still have the very good D7000. Do you buy the older camera and better glass, or do you buy the newer camera and wish you had money left over for newer glass? This is the same conundrum we've had at every model upgrade step. I'd argue that some people are better served by buying behind the curve and using the savings to upgrade other aspects of their photography. But that, of course, isn't the American way. We didn't get to be the world's leading economy by ignoring the latest and greatest gizmos, after all. Still, don't pass over the D7000 just because it isn't the latest model. As always, consider your needs (both current and future) carefully, and decide wisely.