Blogging Libraries- Lists by library type, from blogwithoutalibrary.net.
Library Weblogs- Directory categorized by geographic location, compiled by Peter Scott.
RSS(sm): Rich Site Services- A categorized registry of library services that are delivered or provided through RSS/XML, Atom, or other types of web feeds.
The Blog- Overview of blogging for librarians by Rachel Mathieu and Robyn Fleming. Includes a directory of library blogs.