If you're lucky enough to still shoot with film or one of the new FX bodies, then instead of spending that kind of dough on a lens that would likely be used for landscapes (i.e., on a tripod and taking your time), then I'd recommend spending the money on three prime lenses: the 20mm, 24mm, and the 35mm.
I cannot wait until a D700s is unveiled. I'll go back to shooting mostly prime lenses at that point and never look back.