My experience with it was really different. I didn't read GTD first. I read this: http://www.brool.com/index.php/using-org-mode-with-gtd. Then I read this: http://members.optusnet.com.au/~charles57/GTD/orgmode.html. I thought, hey, this idea of having a trusted system and getting things I needed to do out of my brain and into the system might really help. I also loved the idea of putting my todos in contexts like "home" "office" "lunch" "driving". Those two simple things really made a huge difference for me...