... I do make an effort to leave at least a few comments a day on the posts of others but I have to admit that it is among my circle of friends.
Nothing wrong with this at all, I guess it depends how many friends you want :)
Should we consider qualitative measures of comments as well as quantitative?
We should, but it is easier said than done.
Any ideas on how to do this, (other than just discounting 'nice post', and 'upvote plz sir') would be appreciated :)
Word count would give you an idea, and I think (don't know) spam detector software would weed out posts that were too similar. Also whether the comment was responded too and how many times. Quality comments usually get responded to and a thread is created with more than two entries.
I think the above would definitely help guide, but there are always anomalies. I think quality is in the eye of the reader, and that's really tough to assess with code.
Absolutely:):):)