It's the host, Jive. I think anyone can mark something as helpful, but only you can mark your own thread as assumed answered or mark a particular post as the answer. An Administrator can also do all that I believe.
Soon the board will be upgrading to the latest version and I have no idea whta works or not on that as we only have limited access to the beta thus far.
Thanks for the useful webcast!
Can you provide this video in a HD quality, because it's not possible to see the screens on webgateway demonstrations.