I was just wondering, do SM decide which guests they ask to the event or do they invite everyone and then leave it to the guests to decide whether or not to go? It may seem a stupid question but I haven't a clue.
Personally, I think we're very lucky that guests are willing to come back often. Each time there's a new Q&A session it's a whole new experience. Don't think I'd ever get tired of hearing new stories from the LotR guys.