I wonder what the average ratio of lurkers to posters is on message boards of various types, and how it relates to the perceived friendliness of the board - ie does somewhere busy, aggressive and lightly modded like Bluemoon have a different ratio to a quieter, more genteel site like this one (whaddya mean, it's not genteel - rag!)
There must be a pointless research project in there for some wannabee university that used to be a technical college.