We knew this was coming, Google is transitioning their webmaster hangouts from Google+ Hangouts to YouTube Live Hangouts. I am just happy that John Mueller and friends decided to keep it up and not stop the hangouts because of Google closing them on Google+.
The first two hangouts were scheduled by John Mueller and posted on Google+. John asked you post your questions on Google+ because YouTube Live's version of Hangouts is missing the QA feature that Google+'s version had.
The first one is on September 20th and the second one is on September 23rd, here are the embeds:
John said:
Add your questions to this Google+ post. This session is open to anything webmaster related like crawling, indexing, mobile sites, internationalization, duplicate content, Sitemaps, Search Console, pagination, duplicate content, multi-lingual/multi-regional sites, etc.This is a Hangout on YouTube Live. To join live, watch out for the link here once the event starts, and use a webcam + headset.