This is a critical issue. In this short nine minute video, Eli Pariser says “Your filter bubble is your own personal, unique universe of information that you live in online. What’s in your filter bubble depends on who you are, and it depends on what you do. But you don’t decide what gets in — and more importantly, you don’t see what gets edited out.”
This also applies to attempts to develop algorithm based systems for learning. We have to make sure that people are encouraged to challenging ideas, rather than just following the pathway of least resistance (which is yet another reason why I worry about simple taxonomy driven system).