Not the gp, but I believe the idea is to stop displaying long columns of code like so much wallpaper and instead treat it like the directed multigraph it actually is.
What does that mean? I can't think of any graph-editing GUI that I'd want to use to write code.
There's a reason I still do my graphs in dot, and not in some WYSIWYG editor -- it's much easier to manipulate them.
I don't know. I don't think it exists yet. But have you ever seen an expert using etags/search/debugger/etc to bounce around a large codebase? The location of the functions in the file hierarchy doesn't matter at all. The important graph --the important graphs-- are latent in the code itself.
Bingo.
It makes you wonder why we store code in linear text files, when something more similar to a database seems a bit more apt.