Every blogger has a “Comment” policy, written or unwritten. As “public sector” bloggers, we have responsibilities (to readers and employers) beyond our own narrow personal preferences.
I really like the Rules for Commenting that are posted at the Multnomah Law Library’s Social Software Policy for Multnomah County Library Users, and generally adhere to them myself:
Excerpt: “Rules for commenting
Protect your privacy. Do not post personally identifying information. Young people under age 18, especially, should not post information such as last name, school, age, phone number, address.