I set up a test of a couple lenses I have for the D200. I thought you may all be interested in the results. I put the camera on a tripod and shot two images exactly the same with 2 lenses. Both were focused on the same location. One I shot with the prime 50mm 1.8 and the other with the 17-70 ED Zoom lens. The shots below show the image at 100% with no Photoshoping. I was surprised at how much better the Prime lens was. You could get a very good 20x30 but not with the ED zoom. I was also surprised at the color differences. the prime was much smoother and more natural. Interesting Ehh..
Full image
50mm Prime
Nikon 17-70 ED