I am sure the OP is correct in assuming a lot of people will question their need to move to FX, that is if their main purpose was lower noise at high ISO. That was my main reason for creating a savings jar to get a D3s. I did not like the idea of having change most of my lenses but did want the low light performance a great deal. Otherwise I am quite happy with the D90, with the grip it feels great in the hand, balances well with 70-200 and works very well. I was never bothered by having a few items on the menu, for event and club shooting, I never go to the menu, all I ever need is right on the body of the camera without removing my eye from the VF. I surely get more keepers and do less fiddling with menus than my friends shooting 7D and 5DII in the same events. If I really needed AF mode control, as a dedicated control, the only thing that is missing from this level of camera but present in a Pro unit, I can program the function button to rotate through the choices. So for me, the D7k is a very exciting new toy that I can afford, plus possibly the 24-70 I've been wanting, and maybe the 85 1.4 AF-S to replace my 17-55 and 85 1.4D and have enough money left over for a nice vacation from what is in the jar now. Without the grip, the D90/D7k are a little small for me now but when I first got it it was perfect. The difference is now I keep it in hand for 5-8 hours some nights and it just feels more secure and comfortable with the grip, hand strap and RS-5, usually with a 70-200 attached. When playing with the D3s, I found that it was a lot lighter and compact than I imagined, great feel, but not much different in weight and size than the D90 with grip. Both such set ups feel better, to me than the D300/D700 class body without the grip.
I think the mass of the market is in the mid and entry line, which has a lot more reason to see the D7k as a game changer than those who already have FX glass. So, this camera really is very significant for possibly millions of people despite not having much appeal for the hundreds of thousands who have FX now. So there really should be no impact on either class of camera, the masses, like me will be happy with the D7k and those who want a larger body with a couple more buttons will not change, their upgrade path is secure, but just at a slower release cycle. There enough difference in the product lines to appeal to two different users. One class just happens to be 10 times larger so this cycle got the most attention this time. In the spring the buzz on other brand forums will be about trying to find some faults in the new Fx body just announced or leaked. Nikon is definitely on the right track and causing some hand wringing in boardrooms in Asia. Canon is likely to get its bread and butter mid line eaten for lunch. Stan St Petersburg Russia