With the rearview mirror firmly in hand, one could give Nikon's product strategy with the D3x some thought.
From looking at the feature set and pricing, the aim for the D3x project must have been squarely set on Canon's 1Ds series. It's a good guess that Canon's dominance on the pro side had been noticed at the Nikon exec level. The decision to make a 1Ds competitor was probably taken some time ago, maybe 2-3 years ago. Nikon engineers seem to have succeeded in making a better camera, but last fall A900 and 5DII happened, altering the game: More megapixels doesn't necessarily mean more bucks.
Nikon now has some tough marketing decisions to make: How to follow up D3x with midrange offering using D3x chip, and where will D3x pricing go?
The first one seems obvious at first glance - upgrade D700 body with D3x chip (let's call it D700x), price it just above A900 and 5DII as it's a better built pro-spec body. Maybe start at $4K list price and let it slide down from there.
The second one is trickier. Is D3x seen as a source of revenue, or is it only about bragging rights? With a D700x body on the market as a volume 20+ Mpx product, the D3x becomes a specialist offering instead of enabling technology for Nikon lenses, so there would be less price pressure.
Now, what if Nikon product strategy had gone the other way? Release D700x first, get the volume and market share it would deserve even at $4K price point, then later on release an overpriced D3x for those who need it. I think there is a good possibility that such a strategy would have generated significant volume sales both in pro and prosumer markets, as well as bragging rights for the best DSLR IQ on the market. D3 would remain PJ and sports shooters' choice, and a D3x body (with D3-like frame rate, possibly priced at $10K) would be for those who really need it.
Bottom line - Nikon might have made a strategic mistake here.