marketing webinar
http://blog.getsocial101.com/usinggooglehangoutforwebinar
You can air your Hangout publicly. You can record it, edit the recording, and share the recorded event on the web.

There are so many ways for small to medium-sized businesses to use hangouts to connect with their clients, construct their brands, increase profits for their businesses, and create buzz.

You might have a newsworthy announcement – a new hire, a new product, or to announce that you’ve won an award, hangouts let you tell the whole world and have an interactive record of the announcement.
Using Google hangout for webinar

Press conferences Taylor Swift hosted a hangout to announce her newest album. As soon as her single was published it went straight to number one, more quickly than any other song in history.

http://blog.getsocial101.com/usinggooglehangoutforwebinar

related online webinars videos
http://youtu.be/cQe5ct9oK9g