As promised the first developer preview release of the GUI client is on GitHub. As expected its pretty barebones right now and only suited for developers interested in kicking the tires and poking around the architecture.
I recommend reading through the Mocha test output by opening public/test/TestRunner.html in a browser. That will give you a good idea of what all the different components are responsible for.
I’m working on packaging it up as a desktop app most likely as a Chrome Packaged App. I’ll be testing that approach out over the next few days to see if its got support for everything the app needs. Really excited to have this preview out! Cheers!