Nikon D700 and D300s have been officially listed as discontinued on Nikon Japan.
D700′s replacement model could be the D800. With lots of rumors going on lately, the D800 could be released at the CP+ 2012 Camera & Imaging Show. However, there is still no reliable information about the replacement model of D300s. Perhaps Nikon will shockingly come out with a D400.
For whom that still don’t own a full-frame DSLR, go grab a D700 when D800 is out. The price might be reasonably low.