I attended the Google Hangout Rudai 23 held, and thought it was a good experience. It was a further dimension to enable participants to feel part of the community, although as could be expected rather dependent on internet connection & equipment working well!
This is a tool I could try at work. We have distance learners who call in for help and to be able to chat face to face coould be more useful. I will find a learner with a webcam & a Google account & try it one day.
As for Periscope, this is increasingly popping up in my Twitter feed, though I have never been able to watch one live. The best one I saw was from the BBC (so excellent quality) giving a quick tour of a Waterloo exhibition wth the curators & Dan Snow. While I don’t think I’ll use this (not camera shy, but I am video / voice shy!) I will be watching again – especially if they extend availabilty beyond 24 hours.