I understand that it is good to have a digg, but as only the top diggs get shown on the first page of digg, is there a difference between having one digg and 5 or 6? Can it help in any way with my PR or search engine optimization?
only if it is related and interesting to the digg crowd....look at the site and see what kind of stories make the front page.... if you submit crap, they will delete it
It won't help for the pr directly cause they are nofollow but people may link your site if they find it interesting.