AJ Kohn talks about participation inequality online in his defense of comments, using a number of level-headed metrics, as part of his argument that comments are good for blogs.
A small amount of creators are responsible for the vast majority of the content we consume. They have a limited amount of attention yet wield a lot of influence through their ability to reference sites, products, brands or content in the content theyproduce.
Creators hangout in (aka devote their attention to) the comments section of their content and that of others. Thus, memorable blog comments that provoke creator curiosity (and clicks) build your authority and improve your chances of gaining a mention or link in their content in the future.
I do question how often it’s truly the creators in these comment areas versus reactors that are keeping tabs on creators. Still, I think that’s a valuable audience, and comments are better than Twitter for them to express their opinions with long term value.