In our first prototypes we used a more serious rendering style (it is still available in the interface). It turned out confusing to some more casual users without much experience with digital maps that we *distort* our maps. However, by turning to the non-photorealistic style we make it much more obvious that these maps are just sketches and they are not to scale. The NPR style conveys this idea nicely and makes the maps more easy to understand for non-expert users.

Oh, and it also looks cool, of course 😉

2nd I think the computer emulation of hand-drawing is a legitimate device. Making it look hand-drawn provides a powerful subliminal "clue subtext" — namely, that one should not expect the map to be complete, entirely accurate, proportional, or to scale — all thing we blithely assume about printed or on-screen maps.

3rd I think we should take every opportunity to encourage cyberneticists who are reintroducing the approximateness and imperfections of craft into computer-rendered material. The asymptotic mythology of perfectionism promoted by the plethora of computerized typography, pervasive flawless orthogonality, etc., was really starting to get out of hand (pardon the pun).