Re: In this case, it's just a matter of configuring what's already there
Yep, this sounds like yet another WebRTC implementation. I hear about a new "secure video chat" service about every other week these days. Even Mozilla baked one into the Firefox browser itself. I thought that I might get a break over chrimbo, but apparently Herr Dotcom needed his dose of publicity this week.
The problem with the current crop of WebRTC clients is that, while the conversations are direct between clients in a p2p manner, they need a centralised server (website) to provide the routing of calls (aka call metadata), by virtue of the web browser security model.
The most interesting project to me in this space is Tox which, while still being in a rapidly-developing alpha stage, appears to be well functional for text/voice/video chat.