I'll second Phil's idea with the 70-300. Great lens for the money.
If you do decide on the 80-400, don't be afraid to buy a used one from a reputable dealer. You should be able to save @30%. (it's WAAAAAY overdue an update too, so might be worth waiting?)
btw,He who dies with the most toys, WINS!Nikon D800E & D700 bodies + Nikon 200-400mm F4 VR1, 50mm F1.4G, 16-35mm f/4G VR, 105 F2.8 VR macro, 70-300mm lenses. A couple of filters, Giotto tripod & ballhead. Lowepro Slingshot 302 AW