I'm working on a school project using salesforce right now, and it's basically what you describe, with making a web application through a GUI. It seems like it's probably a good solution for a business that needs an information system without much customization required, since it does make assumptions that can be constraining. I didn't enjoy working with it; it's less fun than programming with text. And I'd tend to call it "application building" rather than programming. Warcraft III's modding tools are similar - they let you build a game without very much typing. (In that case, though, the GUI didn't sap the fun out of it - probably because there was more room for creativity in Warcraft.)

I think there may be technical constraints in making such an interface customizable enough, though. Salesforce and Warcraft make a lot of assumptions about what sort of program you're making. An application-builder that's as general-purpose as a programming language sounds like it'd be really hard to build. (Although I'm not sure how much harder that is than just building something like Drupal.)

We also don't have a graphical way of describing behavior, that I know of. Even in tools like Salesforce and Warcraft, custom logic is shown as plain text (though Salseforce gives you some buttons to insert variable names and operators). It sort of makes sense to just use text, if the alternative is making people learn a new set of symbols.