While interactive graphics can be created in IDL, you are currently limited to distributing an IDL application to provide them to others. It would be useful to be able to create interactive web graphics from IDL — particularly if it was just a click or ->save call from function graphics.

Bokeh is a library for Python capable of generating Javascript to display interactive visualizations. Check out its gallery for examples. Bokeh has bindings for other languages; all that is required for the language is to output the correct JSON to the Javascript part of Bokeh. Bokeh is BSD licensed so it could be used in a commercial product like IDL.

Of course, Bokeh can be used via the Python bridge right now, but that adds an additional burden to its use.