I am very heartened to see that the D700's on the UK eBay site have not dropped at all since the D600 was launched. One went this evening with 48000 hutter clicks for £1000 ($1500 approx.) and yesterday one with 10000 for £1350! Since I sold mine the D800 has dropped considerably in the UK, but if I'd waited I would have had the lower cost of upgrading.
I think serious photographers understand the value of the D700 and what a great camera it still is. Plus of course it's a full semi pro build quality dSLR.