Muzzz's schemata inspired me to calculate one myself. It's the number of posts, the number of words (loosely, but consistently calculated - ie: includes signatures + quotes + webpage text, but does so for everyone), and the avg words per post # (the higher the #, obv, the more verbose the posts). If Mafia stand to gain from lying low, it will indicate those who have contributed the least. Moreso, at least for me, it will help weigh my votes -- both to encourage the quiet to come forward and because a non-contributing player is a better lynch target for the first day, it seems to me, than a highly contributing one.
Korlash 34 Posts - 7690 words (226 wpp)
Wolf 31 posts - 2598 words (84 wpp)
Delathi 30 Posts - 4963 words (165 wpp)
Muzzz 28 Posts - 4189 words (149 wpp)
Porkens 25 posts - 4839 words (194 wpp)
Mordy 24 Posts - 5651 words (235 wpp)
Platypus 21 posts - 2511 words (119 wpp)
Archaist 11 posts - 1678 words (153 wpp)
Phelan 10 posts - 1512 words (151 wpp)
While it's clear that Archaist and Phelan have fallen way behind the other players (in both # of posts and words written), I think it's notable that Wolf has a tremendously low words-per-post number compared to everyone else. (Platypus has the second lowest.) If a Mafia member were trying to post frequently to assuage suspicion, but still didn't want to give too much away, posting very little over a large period might suffice to give the illusion of activity, but without accidently giving away tells.