About HTML5 the latest being microsoft switching its focus from Silverlight to HTML5
With HTML5 media support now websites can now deliver rich, interactive media as easily as they deliver images. Safari was the first browser to support HTML5 audio and video elements
Work is being done to which will enable videoconferencing from HTML5 applications. It will allow the user to give permission to a page to use a device, such as a video camera. That will make possible for users to communicate with each other through a web conferencing from the browser itself. Until recently there was limited support for HTML5 specs but now we have chrome, firefox, opera and IE 9 supporting HTML5. Also there is support for Previous versions of IE through a plugin.
You can read more about it here. http://goo.gl/i3VY.
You can view a demo of video conferencing implemented using the device element and stream API’s in WebKit GTK+ that enables you to capture video from an web cam and display it in the video element.