Today I downloaded a copy of the Blueprint theme: http://drupal.org/project/blueprint. I had been looking at the blueprint css framework as I have to familiarize myself with it for an upcoming project.
With drupal 6 you can use the theme_submit() function to change the value of submit buttons, including those on the node forms without issue. The same cannot be said for theme_submit() in drupal 5.
theme_submit()
