I believe there are strong overrides built into browsers, based on the idea of not wasting ink. So background colours (and therefore text colours) are likely going to be overridden. I expect a white background on a printout and therefore black text.

Having said that, I would expect things like borders to be shown, and rules causing elements to be hidden (or revealed) to be respected. On my own sites, for example, when I print the contact page, the left column and some other elements are hidden when printed. This is what I have in my stylesheet. It's not working right (some content slides up under my logo) and I have to fix it now (thanks for bringing this subject up to remind me ) but it is doing what I told it to do in the print_stylesheet.

Rob