Time magazine, or one of those sort of things, had a huge article on Abraham a few months ago. It basically said that his break into monotheism (while not the first) was possibly the most influential move in human history.
Update:
http://www.time.com/time/covers/1101020930/
It was the cover story on Sept. 30, 2002. The above link will take you to where you can purchase it, but i figure you can just go to your local library and check it out.