> Non-destructive editing is not a "nice to have" feature. It's quite literally a fundamental shift in methodology - and one that apparently the GIMP devs seem to be ignoring.

It's on the http://wiki.gimp.org/index.php/Roadmap , UI designer Peter Sikkings has written a lot about how one might do it http://blog.mmiworks.net/search/label/GIMP%20redux and one of the main selling points of the move to GEGL is non-destructive editing. And all the focus now is on the move to GEGL.