goog+ have just added voip video conference capabilities to goog+ hangouts and have also created a hangout extras beta for screen / window / notes / whiteboard sharing

• google.com/support/plus/bin/static.py?page=guide.cs&guide=1257349&topic=1651183&answer=161993&ctx=go&hl=en_GB
• google.com/support/plus/bin/answer.py?hl=en-GB&answer=1289346&ctx=go&hl=en-gb
• google.com/support/plus/bin/answer.py?answer=1660619