Uh, it’s nice I’m sure, but it’s not in-browser Web Sockets. For a start, the majority of new browsers have turned off Web Sockets while a spec security hole is dealt with. Secondly, half the browsers they list as supporting don’t have even support to turn off in the first place.
It is in-browser web sockets. It falls back to a flash implementation of websockets if the browser doesn't support it natively.
It's also completely over SSL, so the transparent proxy security bug does not apply.