Buy cheap, buy twice. Save your money like C Dave said.

Two things to consider:
1) What youhave to realize is that not only are you getting a two stop faster lens w/the 2.8 but you're getting VR w/it which will add an additional 2-3 stops to it.

2) This kind of goes against the speed that you're asking but it makes more sense to get the 80-400 VR, yes its slow but every single wildlife photographer friend I have has never complained about havingn too long of a lens. 200 is short even w/the 1.5 crop factor.

If I was you, I would save, buy the 80-400 VR and a good bogen or slik tripod w/a good ball head. I shoot Canon and I have the 100-400 and many many times I needed more. The 80-400 and the 70-200 are two of Nikon's sharpest zoom lenses so you won't go wrong.

Hope this helps and let me know if there's anything else I can help with
Scott