Speaking for myself, I find this greatly helpful as I find it limiting to try and force a set of ideas into an orderly list right away. Later on I might make an orderly list, but the most helpful thing is to first map out the relationship between different ideas. It is from that map which I make orderly lists, and it is through making the map that I can find clues telling me how to organize the thing being written, what points to cover, and even more about the purpose of writing.
For more on Mind Mapping, see http://www.mind-map.com/