If that's too hard, at least understand the summary on Wikipedia: http://en.wikipedia.org/wiki/The_Wisdom_of_Crowds#Four_eleme...
A quick look at your site and it's clear you don't get point #2 Independence as you're showing people the prior avg before they submit their answer. I'll bet your site will suffer from a lack of #1 Diversity of opinion as well, as most websites tend to gather abnormally high concentrations of like minded people just through the natural ways they acquire and accrete audience.
I was hoping that because there are many answers above the folder, it might negate information cascading.
Lack of diversity will be definitely be a problem =D