Just a data point for the TalkBoard members: as is typical with many fora, there are significantly more reader-lurkers than members reading.
Typically, those who choose to un cloak and emerge from lurker space
post with a "been reading a long time and decided to sign up" followed by a statement or request for assistance.
I have no clue what the numbers are for lurkers as a membership source, but currently (08:05 Pacific) MS has:
Showing threads 1 to 25 of 1871 / 130 (39 members & 91 guests) / Moderators : 3