It is posted to /r/cogsci and /r/math, both good communities for their fields (the average commenter seems to be at least at a junior's level by my own subjective judgment) . Due to the the drop off effect experienced in people trying to lose weight, watch open source lectures (look at the total views from beginning to end in this Harvard course for instance http://www.youtube.com/watch?v=kBdfcR-8hEY), or generally do things that aren't easy I expect to see high quality redditors commenting rather than the memes common on the front page.

I'll be joining if that helps your decision, my username there is the same as it is here.