I'm a yEd user, and I've started to use it for my job which involves visualising information as a substitute for traditional documentation. I chose yEd because building information structures graphically in GraphML means I can fit it into the XML publishing pipeline; but if I can't retain those grouping relationships in a graphical output then its pointless. Right now SVG and HTML exports are only static with tooltips at best, but I can't close or open groups to be able to output the whole diagram in the same way as its seen in yEd. Using SWF is not an option because it will become obsolate; but if yEd is already outputting in HTML and SVG, there's no reason why they can't create an export option to retain all the interaction using javascript, or directly HTML5.
I guess I could try create a converter myself; but due to lack of time in my job I am starting off with just XSLT transformation of GraphML to interactive SVG - not export SVG from yEd which is only static images.