Sometimes its not enough to talk, sometimes you have to ask questions. There is always going to be someone that wants to show how smart they are. You just have to give them the chance to post something and show off.
[ame=http://www.youtube.com/watch?v=_jv8YryPiBc]YouTube - Wilderness survival quiz ID this berry[/ame]
To change my video series up a little bit, I'll post a "quiz" type video and ask for the answer. These types of videos usually get lots of comments.