python guis with avc

avc looks like an interesting concept. it's a pure python library that connects gui toolkit variables to variables in the scope of your python script, with bidirectional communication. looks like a very clean and easy way to separate the view from the logic, and it has a standardized interface for gtk, qt3, qt4, tk, and wxwidgets. tk doesn't look as good as the others, but it's easy to get with python. gtk and wxwidgets look like the most feature-complete. all of the toolkits have their own optional external interface def files, and avc can use those. but you can also set up everything from the comfort of your python script. only problem: it's gpl, so i might need to use something else if i want to sell my stuff. EDIT: i think enthought's Traits might be usable in a similar way. and if i'm not mistaken, they license their open source stuff bsd.