Please let me know if you have suggestions for the site, thanks.
This method won't help of course so in the future you'll need to distinguish so people as "experts" (this is a human task, it can't be awarded statistically - by a number of reviews or anything similar). After that implement separate rating for them.
Even that won't fix biased reviews but will mitigate them considerably. The task of implementing good rankings is a very hard one.
Maybe you can talk to the Udacity/edX/Coursera guys to get some kind of API access? Regardless, this is awesome - I've taken two courses on Udacity, and love it so far. However, there has been an explosion of courses offered so it would be nice to have tools like this to help me filter.