A D1h is still capable of producing very acceptable results, although it is dated. The main reason for upgrading is not, as most people seem to think, the number of megapixels, but the contrasts it can master. (Although some are convinced it is number of the frames per seconds as most people seem to be sports photographers that produce images for magazines like Sports Illustrated) The dynamic range of a camera has been the main breakpoint for serious photographers; that is why cameras like the Fuji S3 and S5 have been sought after for so many years after they disappeared from the market: their digital range has been better than anything else on the market in those days.
The race for more and more megapixels has mainly been a marketing tool. About 98% of people never need anything larger than a 6 megapixel camera, but just buy it because someone else has one.
Just a few people need the D800, for just prints on the web, like most people do, everything else is like killing a mosquito with a gun. (Although it can be fun, shooting mosquitos this way)
