Nikon D4s unboxing: It’s arrived!

The D7000 replaced the D90 as the top consumer DX model. The D300s is the prosumer/pro DX model, and sits above the D7xxx models in the line-up. It hasn’t been replaced yet.
Likewise, the D600/610, are consumer FX models (essentially the same bodies as D7100), whereas the D700 was a prosumer/pro FX model, which was, arguably, replaced by the D800. Some people still wait for a ‘true’ D700 successor, though.

Source Article from http://www.dpreview.com/news/2014/03/13/the-nikon-d4s-is-here