[pcmonk]

I've personally been pulled into another project, but I do think there's plenty of unexplored space in the structured code editor arena. Paredit is good, but I'd like to see a more visual way of dealing with the structure.

The challenge is, of course, that a general-purpose tree editor is not likely to be efficient for editing code. You have to resist the urge to over-generalize. A good structured code editor isn't likely to be useful for anything besides coding.