The newest edition of the Bluebook will be released this month. According to Wisblawg (quoting Hein):
the 19th edition retains the same basic approach to legal citation
established by its predecessors. The layout has been updated to make information
easier to access. Some citation forms have been expanded, elaborated upon, or
modified from previous editions to reflect the ever-expanding range of
authorities used in legal writing and to respond to suggestions from the legal
community.