A very good Nikon D200 D300 comparison
Steve Bingham, a great photographer in Payson, AZ performed his own test comparing images from a Nikon D200 and Nikon D300. The test are across multiple ISO values under low-level tungsten light. It is one of the better comparisons I’ve seen since it reproduces the type of light that is a challenge to shoot. You can view his test results at http://www.dustylens.com/d200_vs_d300.htm
There is an active conversation at DPReview about it now – http://forums.dpreview.com/forums/readflat.asp?forum=1014&thread=26310278
I plan to do some of my own comparison shots and include the D70 when I get some time. I want to focus on color and dynamic range differences.