The other day someone sent a message about a list with about 900 subscribers, indicating that it was a somewhat large list. What would be considered a small, medium, large list? Wouldn't the focus of the group (more popular v more esoteric subject matter) have an impact on how large a group might be? Additionally, has a predictable rate of growth over time been noted in connection with these groups. Does anyone know of any literature that addresses these issues? Thanks, Paula