Did I mention that Democracy for Pittsburgh has endorsed Joe Hoeffel?
It is very interesting to read their rules for voting. You have to have been to two DFP meetups or attended two events since February 2009 (within the last year). I think that's a very reasonable way to avoid the endorsement vote being packed by "sudden" members. Endorsement requires 70% vote and vote counts are not released.
From casual conversation with members of various "clubs who endorse" my undesrstanding is that vote packing is a longstanding tradition. Sad to say. I'm not in favor of people being able to walk in off the street, pay cash and cast an endorsement vote. I think it is ripe for fraud and damages the credibility of the club/organization. Attending an event or two over the course of 12 months is not an arduous burden to meet for voting privileges. It is incumbent on the organization to avoid the appearance of impropriety (along with actual impropriety) and DFP seems to have a threshhold that's reasonable.