I only use the home screen. I have Pure Calendar widget on a second screen if I am too lazy to go to the calendar, but really I would say I only use the main screen.
I have the 2.1 News/Weather widget (wish I could choose who I want the news stories to come from though ), the default power strip widget (I think it goes nice with the smoked glass and the default rocky looking gray background), four App Organizer "folders", the phone icon, and one 1x1 More Icon widget. And I still have an empty space.
Are those of you using 4-5 screens just not using app organizer/more icons, or should I be using more "cool" widgets that I don't know about?