I guess the question is: If there's a $3000 FX camera, will you buy a $2000 DX one?
Maybe? For me, such a camera just might need built-in stabilization. I can hold the D300 + Sigma f/2.8 down to what I think are some really low shutter speeds, but if you peep closely, the results don't compare with 70-200 VR in low light, and my hit ratio isn't going to improve with twice the MP. At the very least, the standard zoom needs it, but I see no problem putting it in the body, which has it's own advantages, even for companies like Nikon and Canon.
There's no 17-55 VR... There's no 24-70 VR either, but the bigger pixels/sensor should be just a little less critical of both high sensitivity, and focus/stability. I would have to carefully test the newer third party stabilized zooms as APSC resolutions continue to creep upwards. Sigma and Tamron both have new models to review. Interesting that Canon's had a 17-55 IS f/2.8 from the beginning, I think they recognize something here beyond just the marketability of stabilization, and there's some rumor of an f/2 17-55 patent from Canon! But I haven't seen it, and it doesn't mean they would build it either.
Their 24-70, like Nikon's, is also without stabilization: my suspicions might be correct at current pixel densities?
Maybe I should try Nikon's 17-55 again, people say it's very sharp. It could be that I'm completely wrong, and I'm just seeing wide open softness in low contrast lighting on the Sigma, and though I'm at low shutter speeds, it's not my hands, it's the light itself. In bright light, wide open, the lens is sharp: shutter speeds are faster, but contrast is a lot higher too... hmmm... The Nikon 70-200 isn't just stabilized, it's more neutral in color (doesn't warm-up as much) and it looks like it deals with contrast better. The best comparison might be to put both on a tripod (VR off on the 70-200) and shoot a somewhat unscientific comparison of their low light rendition.
Coming back to the DX vs FX question, it may depend on the lenses. Someone with need of a 100-300 f/2.8 for outdoor shooting, may indeed find the DX option more attractive. Me, I really want my 85 to frame like an 85, and a 35mm that does the same... I think I can continue living with a DX standard zoom, but I would like the ability to throw the background focus a bit more...
In our program, the college supports three platforms. Canon, Nikon and Hassleblad. Everything else, you're on your own. It's one reason Canon and Nikon aren't as troubled by Sony as they should be. They're imbedded in the industry, but that can turn around fast if instructors start requesting Sony or other equipment, which brings up a side note on Sigma - Foveon is the only other technology that's referenced at all in course materials...
I really like the built-in SSD idea. Around here there's this whole orthodoxy around card storage/data transfer. People freak out if you plug a camera into a computer: "you shouldn't transfer files that way; it could corrupt the card; you could lose an assignment!" To be honest, I never though about it. I've always plugged my camera into my computer. They make you buy a card reader by 2nd class, so at least one generation of digital photographers has a conception of best practices that treats cards very carefully. A camera that automatically backs-up your last card would be a lifesaver to these people.
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