Just found this site linked to on another forum:
http://home.comcast.net/~NikonD70/Charts/PDR.htm
On another thread I mentioned that I shoot at ISO values that are multiples of 160 (I have Canon 30D and 5DII bodies). These values also seem to have the better DR than even ISO's such as 100, 200, 400, 800 etc. Of course it isn't the same for all brands/bodies.
This information may be more interesting than useful.
Glenn