Brian makes some good points and gives some good advice.
In your second post you mentioned the 70-300 VR. I think this is one of Nikon's most under appreciated lens'. It is light, has a very useful focal length, takes 67mm filters and the two I have owned were extremely sharp. Since weight is important I would seriously recommend this lens. The only issue may be the variable aperture vs the 70-200. However again, the weight difference between those two lens' is significant. If you decide on the 70-300 I think you will be very happy.