A human need for fiber?

Well after attending AHS 2012 the other week I came home with more questions then I could have imagined going into it.  All of the presentations were fantastic, however the safe starches panel seems to be the most talked about.  This was very interesting, as it seemed like the panelists covered almost the entire spectrum of a carbohydrate intake continuum.  Another point that was brought up was the need for dietary fiber, and, being somewhat unsure about this topic, I decided to dig a little further into it.