Mike,
I finally got the Nikon d70s. Thanks for the help in the decision process. In reading the manual they suggest using a white card for WB. Do you feel a grey card is better?

Richard:

My manual, on page 52 for preset WB, indicates: "Neutral gray or white object is placed under lighting that will be used in final photograph and white balance is measured by camera."

So, I suppose either would do the trick. The question in my mind is: which white? I've not tried using a white for the preset measurement, maybe the camera is smart enough to figure what it needs from any white, but to me it seems reasonable to eliminate as many variables as possible.