This is interesting. Superficially at least, it reminds me of MAX/MSP or PureData, which are used to create music and other media. For me, it has the same shortcoming: it is very 'mousey', and with MAX/MSP and PureData at least, I grow tired of using them quickly because of this. Basically, I would like to use the keyboard for everything. Still, I respect the work, and I imagine this type of environment could be given a (perhaps VIM-like) mode that could enable keyboard selection and chaining of widgets.