I wrote a visual Songwriting page at my https://www.harptab.com site Visual Harmonica Tab Songwriter.
I wrote one for guitar tab, too: Visual Guitar Tab Songwriter
I have now conquered drag and drop (without benefit of some bloated framework) and I am thinking of applications where a visual editor in javascript would be a cool thing. It would be less flexible than flash, but very light weight (it would work on iPhones) and I could dynamically create complex web pages and save the results. I am currently writing the PHP code to extract the generated formatting and save it in such a way that it could be revised later using the same javascript code.