Some "visal programming languages" are actually faster to develop, specifically where there are prebuilt components and the real ability to reuse existing work.
Another great advantage is for business people and BAs to be able to easily see and understand how the application works, and even contribute at a meaningful level to what business needs.It's easier for new people on a project to pick up an understand what has been written, rather than getting their head around thousands of lines of code.
While technically not a visual programming language, we're developing an ESB that works inside a visual IDE and uses a lot of flow based and visual programming principles to make it easy to learn and simple to use. It's an open source project, go check it out on GitHub - https://github.com/Warewolf-ESB/Warewolf-ESB or get a compiled version from http://warewolf.io