I still like the representatives from different boards as "gatekeepers." In my opinion, we're over-thinking this. Granted, alot of people feel the SL is "CF's," and even if it started there, the entire comunity of forums as a whole use it and have access to it. As far as I'm concerned, the list is hosted on a website that many different cigar smokers visit and get information about our hobby, so why not keep in that same sense and make it a universal list? It's so simple to me...
It's not "Gartrader's Scumbag List," or "Cigar Family's Scumbag List," or "Cigar Pass' Scumbag List," or even "ICC's Scumbag List." It is all of ours, so lets just get this thing going. As far as criteria, I think that if the respective community as a whole deems the particular individual's actions to be so low that they should be added to the list, then a representative from the community where the "scumbaggery" took place should present their case to the gatekeepers and outline why the individual should be added. The gatekeepers can then confer and decide, and the individual is either added or they are not added.
Where the "representatives from multiple boards" comes into play is that it minimizes personal bias in the decision making, and a somewhat neutral committe can make the decision.
Hope this makes sense, I'm a bit tired....