http://www.bitescrow.org/
How about if to bid you need to get the auctioneer (one of several maybe) to set up an escrow transaction and send out a payment invite to the bidder. The bidder pays bitcoin to the escrow account, and then publishes the address and amount to the thread. The bid is deemed valid when the address hits the thread, and the bid amount can be verified by anyone.
If someone is outbid, the auctioneer sends them the other half of the escrow key.
For the winning bids, the escrow keys are sent to friedcat instead.
No dummy bids, no welching on payments. Anyone buying to flip needs to front the bitcoin first.
Sorry, wouldn't work. You overestimate the general public's willingness to learn. Also, most buyers I know do not have the coins on hand, and transfer them via Gox or otherwise after the auction.
That's a shame. We have this incredible technology in our hands, and the best we can do to manage the auction is a python script that scrapes the auction page looking for something that looks like a bid, combined with a lot of manual effort by your good self and others.
I would actually prefer your way to weed out problematic bidders, but I'll imagine that I would get more PM's on this. Heck, I had to answer a ton of newbie questions even though the auction is so simplified... Honestly many people would never read before asking. (proved during a group buy I escrowed too)