It intuitively makes sense to me that: a) Low-quality comments in blogs are a turn off.
b) I often will privately post something on G+ or facebook. Or even twitter (not private, but hard to aggregate). These options didn't exist back in 2005, which may have been the peak of comments. The article also links to more anecdotes that Techcrunch and somebody else saw a drop-off in comments recently. None of this is saying comments are doomed. In many ways hubski is yet another disaggregated, semi-private place to chat about stories, and that is swell. It's just that comments require care to get right.
This much is true. I think what G+, etc., bring is unity, and that didn't previously exist. That is, the comments have moved elsewhere. I was pretty interested in Disqus at first, but many blogs that were using it (including TechCrunch) switched to FB comments, and I just can't submit my aunts and cousins to comments that I make at TechCrunch. It remains my opinion that a good number of people want to meaningfully engage with others around topics of interest, and the it can be done better than what anyone (including us) are currently doing. IMO that is our most important challenge. How do we make the conversation experience even better?b) I often will privately post something on G+ or facebook. Or even twitter (not private, but hard to aggregate). These options didn't exist back in 2005, which may be the peak of comments.