I very much enjoyed Bret's talk, but the visual programming part of his talk was rather half-baked. I say this as someone who has done visual coding professionally in the past. People have been trying to crack the "drawing programs" nut for decades. It's not a forgotten idea. It's so not forgotten that there is a wikipedia page listing dozens of attempts over the years: http://en.wikipedia.org/wiki/Visual_programming_language.

The reason we still code in text is because visual programming is not a hard problem -- it's a dozen hard problems. Think about all of the tools we use to consume, analyze, or produce textual source code. There are code navigators, searchers, transformers, formatters, highlighters, versioners, change managers, debuggers, compilers, analyzers, generators, and review tools. All of those use cases would need to be fulfilled. Unlike diagrams, text is a convenient serialization and storage format, you can leverage the Unix philosophy to use the best of breed of the tools you need. We don't have a lingua franca for diagrams like we do for text files.

It's not due to dogma or laziness that we use text to write code. It's because the above list of things are not trivial to get right and making them work on pictures is orders of magnitude harder than making them work with text.

EDIT: Wordsmithing