I have been doing GTD for around 2 months now and am glad to say it is working well for me. I have noticed changes in myself, but the interesting question is whether others around you e.g work colleagues notice this too.
I have definitely noticed a change in the work environment around me, for instance being passed more and more work to do, much of which is not even my area of responsibility (thanks to GTD I am just about keeping on top of it ). It seems that people are perceiving me as being "reliable" and "organised" and that if they pass it to me they can rely that it will get done. Not sure if that's a good or bad thing! It reminds me of the line from Spiderman: "with great power comes great responsibility"
I am interested in hearing from fellow GTDers how they have experienced people interacting differently with them as they progress to Mind Like Water.