My largest complaint about polls and discussions is often that they are no more than popularity contests of no substantive value ("worst battle" and "best scenario" threads turn into mere laundry lists of titles). It is strange to see a thread whose purpose is actually a popularity contest and stranger still for me to have no objection to it. Perhaps it is because at this point Mr. Armstrong is in the lead, or because the field contains so many worthy candidates. In the wake of the thread by Jan (Honza) relating the shabby treatment that was meted out to him, this was a nice choice of topic. While I'm still puzzled why I'm not outraged by this, perhaps I'll be angrier in Feb 2012 if Paul Weir isn't one of the contenders.
My write-in vote is Cherper. You didn't say "poster", just member. As an admin, Cherper often gets involved in lots of messiness behind the scenes. Alanp has done the same, though I think has been a bit less active as of late. Apologies if I've gotten that wrong. But both have done unheralded work as moderators behind the scenes and definitely count as "members" in my books, even if their presence is not so flashy out in public.
I'd like to give an honourable mention to BattleSchool as well, who may be under Glennbo's radar, but who has been posting lots of ASL-related material and carrying the torch up in Canada and promoting the game to a great many people.