The original Canon 5D revolutionized pricing and sales volume for DSLRs in full 35mm format, starting at US$3200 and rather quickly adjusted to a bit under $3000.
Since then, several generations of new models from Canon, Nikon and Sony have almost all been released at about that same price level. The latest are a bit more, but this could just be inflation and yen-dollar exchange rates. The exception was the Sony A850, apparently abandoned because it took sales mostly from the higher margin A900 rather than from Canon or Nikon.
The high frame rate professional sports/action models also sem to have flat or somewhat rising prices, while in some cases offering bigger sensors for the price.
So has the 35mm DSLR format, or even the whole DSLR market, matured beyond ever decreasing prices on each new model to a pattern of "even better at the same price"?
P. S. the $8000 price category is gone, but only because the high end full 35mm format high resolution super-rugged bodies with integrated vertical grip in that price range are no longer being introduced, not because new models of that type are cheaper. The latest 16MP and 18 MP highnfra,e rate bodies are not "high resolution" in the way that the Canon 1Ds series and Nikon D-something-X bodies were, when compared to contemporary options.