From Google's official announcement: "Today we're excited to launch Hangouts On Air to Google+ users worldwide.
With just a few clicks, you’ll be able to: Broadcast publicly. By checking "Enable Hangouts On Air," you can broadcast your live hangout—from the Google+ stream, to your YouTube channel or your website—to the entire world.
See how many viewers you’ve got. During your broadcast, you can look inside the hangout to see how many people are watching live.
Record and re-share. Once you're off the air, we’ll upload a public recording to your YouTube channel, and to your original Google+ post. This way it's easy to share and discuss your broadcast after it's over.
Of course, launching millions of live stations takes some doing, so we're rolling out Hangouts On Air gradually, over the next few weeks."
Some very good news, that many of us in education been waiting on for quite a while. Having facility to combine video conferencing with broadcasting and publishing will really extend what is possible in collaborative learning spaces for schools, colleges and educational projects around the world.
Official announcement: http://googleblog.blogspot.com/2012/05/google-hangouts-on-air-broadcast-your.html ;
Find out more: http://www.google.com/+/learnmore/hangouts/onair.
Via Robin Good, theo kuechel, Heiko Idensen