They could cut their costs substantially by going with sub-FF support
lenses, even ones designed for
digital, Olympus's overpriced pro lenses notwithstanding.
Looking that this, I'd say it's a fair bet Nikon is going FF at some
point, maybe soon.

DX lenses:

DX Nikkor Lenses for DX Format Digital SLRs
10.5mm f/2.8G ED AF DX Fisheye-Nikkor
12-24mm f/4G ED-IF AF-S DX Zoom-Nikkor - REBATE!
18-55mm f/3.5-5.6G ED II AF-S DX Zoom-Nikkor
18-70mm f/3.5-4.5G ED-IF AF-S DX Zoom Nikkor
18-135mm f/3.5-5.6G ED-IF AF-S DX Zoom-Nikkor - NEW!
18-200mm f/3.5-5.6 G ED-IF AF-S VR DX Zoom-Nikkor
17-55mm f/2.8G ED-IF AF-S DX Zoom-Nikkor - REBATE!
55-200mm f/4-5.6G ED AF-S DX Zoom-Nikkor

Film Lenses:

Vibration Reduction (VR) Lenses
70-300mm f/4.5-5.6G ED-IF AF-S VR Zoom-Nikkor
200mm f/2G ED-IF AF-S VR Nikkor
300mm f/2.8G ED-IF AF-S VR Nikkor - REBATE!
24-120mm f/3.5-5.6G ED-IF AF-S VR Zoom-Nikkor - REBATE!
70-200mm f/2.8G ED-IF AF-S VR Zoom-Nikkor - REBATE!
80-400mm f/4.5-5.6D ED AF VR Zoom-Nikkor
200-400mm f/4G ED-IF AF-S VR Zoom-Nikkor
24-85mm f/2.8-4D IF AF Zoom-Nikkor
24-85mm f/3.5-4.5G ED-IF AF-S Zoom-Nikkor
28-70mm f/2.8D ED-IF AF-S Zoom-Nikkor - REBATE!
28-80mm f/3.3-5.6G AF Zoom-Nikkor
28-105mm f/3.5-4.5D AF Zoom-Nikkor
70-300mm f/4.5-5.6G ED-IF AF-S VR Zoom-Nikkor - NEW!
70-300mm f/4-5.6G AF Zoom-Nikkor
80-200mm f/2.8D ED AF Zoom-Nikkor - REBATE!