Some folks have been arguing about the difference between the Baker Street Irregulars and Sherlockian fandom.
In this post for Criminal Element, I explain the differences clearly.
(Note: for the purposes of this intellectual exercise, the possibility that the BSI may potentially be a storied and erudite literary society and a happily thriving fandom simultaneously will be ignored. This decision was made in light of the fact that a noun cannot be two things concurrently, the way the Empire State Building is not both a functioning office tower and a tourist destination, and the way Bill Clinton is not both a former president and a saxophone player. Arguments that the BSI is peopled by both cultured readers and by eager fans would only muddy the issue, and therefore will not be entertained here.)