I've had two problems with my D700 bodies that I have never experienced with previous Nikons: -- Hot shoes loosening and needing to be replaced, and -- rubber panels coming loose.
I wrote to Nikon about the hot shoes, but never received a response. I am concerned about the rubber coverings as well. Again -- 45+ years with Nikon cameras and never a problem. Now 3 and a few months with D700s and several issues common to both bodies. In the meanwhile, Nikon is non-responsive.
Therefore I don't think it makes sense to send anything to Nikon and I am getting my repairs done at APS in Morton Grove, IL. They communicate, fix things the first time and get the job done quickly. I've seen none of those characteristics at Nikon's own facilities in the last two years or so. Again, I have used Nikons through decades of military life, on five continents and in 25+ countries without problems. I hope my experiences with my D700 bodies -- which I otherwise absolutely love -- do not portend the future. Nikon put a dent in Canon's proliferation among pros with the D3/D700 family. But if they don't get their service and communication back on track they are going to lose market penetration again. To prevail in the market, you need to offer a great product and back it superbly. I'm pretty sure the latter element is absent and am growing worried about the product as well. My D1X, D100 and D200 cameras were great out of the box and never gave me any problems.