Your image of the pelican is nice and sharp. The shots I've taken with it haven't been as sharp as the one you posted. Have you had any trouble with the sharpness of the lens? I'm beginning to wonder if my lens is very slightly out of focus and needs to be adjusted.
I have this lens and it's very sharp when given enough light to work with. Nice to see the D700 work so well with it.
I haven't noticed a problem with it yet. But I can only vouch for the 700's large pixels, which I've heard is more forgiving of some lens' faults. (while showing others....grrrr)