WebRTC is a new technology that delivers "Real Time Communication" (including video conferencing) directly between web browsers. If you are using Google Chrome or Firefox as your browser you already have WebRTC. If you use Internet Explorer WebRTC will run within it after the installation of Google's Chrome Frame. Unfortunately Apple are not yet supporting WebRTC so it does not run in Safari.
Google Chrome is available as a free download, so if you don't have a browser that supports WebRTC all you need to do is download Google Chrome.
WebRTC was developed by Google. It was open sourced in May 2011 making it available to everyone. Like the Internet itself WebRTC is not owned or run by any single entity. W3C, Google, The Mozilla Foundation and Ericsson Labs are all actively involved in its development.
Yes, WebRTC meets all the currently applicable security and quality standards set down by the relevant regulatory agencies. One of the interesting aspects of WebRTC is that it has encryption baked right into it; there's actually no way to send unencrypted media using WebRTC. VGA picture quality (640x480) is generally achievable with high speed Internet connections giving even better image results.