yes, it is interesting to see how much can be distributed through comments. Did you see this?
Granted many of them are automated accounts, members of trails and the like but still ( I don't know what the hell utopian are voting on though). Anyway, that is a lot of distribution on comments if you think about it and I would say that for the most part (at least for me) the comments I get are generally decent which means that voting on good comments will increase the value of good commentors significantly.
In my experience, it has changed the engagement level significantly, as has flagging spam a bit more often.
I really didn't understand the math behind it, and then when I looked at some of the people above me in the chart, there are some who are big enough that will, even with just a few votes skew the results.
I've noticed that 5% votes for comments won't generally affect my SP too much so I can vote on almost every comment I find good or interesting enough. 85th place... makes me wonder.
I have no idea and yes, the ones above can skew it a lot but, it is an interesting metric to consider (not necessarily how it is presented there). I think that when the hivemind updates come these kinds of statistics are easier to pull and much more will be unveiled.