We are using it at Coldwell Banker in the Southeast (Georgia, Florida, Texas) with great success! It is a great way to do an Open House for your foreign or distance investors/buyers. Also a neat way to do a broker's open. It has certainly worked for a few of our agents who state they have made sales to customers who watched live or who saw their recorded home tour after a friend told them about it.
Suggestions (its all about the HAVES, not the HAVE NOTS):
1 have a plan! In the example of a Q&A, have a second person who is following the questions or comments on the screen so you are focused on the answers. Repeat the question you are going to answer before answering (not everyone is reading the screen) and dont be afraid to skip questions that you dont like/know answers to.
2 Have filler... time moves SO slow when there is nothing to answer!
3 Have fun!!!!! Remember that you are on camera! Smile, laugh, get serious. Facial expressions MAKE a periscope as much as content does! If you are not comfortable on screen, don't do it!
4 Have an ending/out. Ending a periscope, vlog, podcast, etc can be awkward if not planned. Have a short "Thank you for watching, for additional information please blah blah blah blah".
Just my 2 cents... which is what it is worth :-)