I have not tracked the comments I have received on “library posts” vs. “non-library posts,” but I do have an observation. In the late 1990s, I ran a multi-type library organization and I also had a year as the President of the state library association. In both cases, I had a monthly column to write. I tackled various library issues of the day, but often ended with some personal note or another. For the library association it often covered things with my car, which I drove around the state, and hit 100,000 miles that year. I received many more comments, and had much more conversation about the personal stuff than the library stuff.

I think that is because it is the personal stuff that helps to bind us together. We feel we know each other better because we can relate to the car issues, or in your case, enjoy learning more about solar power and how it could be applied on a personal level.

So, I think my observation back to Rachel is that part of why she does not get as many comments on the library blog, is that those folks get to comment to her on FriendFeed and/or Twitter, *in addition to* the fact that folks will comment on the personal as part of the social glue.