Not sure what your budget is, but in terms of value for dollar spent, the new 70-200 f/4 VR Nikkor is going to be a very good deal. Top grade prime lenses are for the most part, now in the $1400-$1699 price range on things like the 35/1.4 or 85/1.4 or the 105/2 or 135/2 Defocus Control models, so...the f/4 zoom lens gives you all the lengths, from 70mm to 85 to 105 to 135 to 180 to 200mm...all in one, single tube. f/4 is amply fast, aperture wise, and the optics of the new lens are pretty good according to the reports I have seen.
The reason I like the 70-200 is for versatility and speed and continuity. Same color rendering across all focal lengths, since it's one lens and not multiple lenses. No need to change lenses. One filter size, one attachment size, and a nice weight to it--a lot less than a 70-0200 f/2.8. It's good on DX and on FX too. With a 70-200 you can find the right focal length to get the kind of background you want, in almost any situation where 200mm is long enough, and in more cramped places the 70mm end is pretty handy, especially on a DX body. I would not worry about the 70-200 f/4 as opposed to the 2.8, or as opposed to how one specific prime lens might be better at one thing.