There's no reason a high-speed, action-oriented, weather-sealed, crop-sensor D400 can't coexist at the same, or even slightly higher price point than an entry-level full-frame body. After all, the 1D2, 1D3 and 1D4 both managed to coexist with the 5D and 5D2.
Alsoi, I'd hardly call the D800 a 'mid-level' body. Mid-priced, maybe, but it has all the features of the top-level D3x and 1Ds3 updated for 2012, plus more. Just that the price point for that sort of camera has fallen (no-one was willing to pay twice as much as the 5D2 for a few extra features), leaving only the high-speed action bodies at the higher price point, since sports photographers are willing to pay for them.
I agree... They (Nikon) could have easily charged more for the 800, since Canon has the price increase (craze) with every new release for L or DSLR's 1d/5Dx...
What they did was smart releasing it at $3,000... I wonder what the 600 is going to sell for.
I paid full price to get the 5d3, etc. I'm happy with it over the 5d2, but with all things said, $3500 was a slightly steep, etc.