Hi Eric,
Marketo does not currently ¨support" Google hangouts in the way that they support WebEx etc, only because there is no way to track attendance of a Google Hangout the way that you can with other platforms.
However, you can still do hangouts in Marketo. To track attendance, you can use a workaround by tracking clicks of the hangout link from a Marketo landing page. This can overcount because people may click before the hangout has started.
You can get custom code written which will provide you with a Join Hangout type of button on your landing page. The custom code will be controlled by a program token, which will change the button from ¨Ḧangout has not yet started¨, to ¨Join Hangout Now¨.
This takes care of only allowing people to click on the link once your hangout is ready to begin, but it is more manual because you will need to physically switch out the program token with your hangout url just before your hangout goes live.
Does that help answer you question? If you like, I can provide the code we are using to do this in our team.