I read the thread about scammers...and I was think about the escrow services...the one I saw seems to refund BTC to the sender if some amount of time passed. I wonder if that's the best policy. Wouldn't it be better to not release the funds until both parties sign off on a desired transaction to close out the escrow? If they don't sign off together, then the funds would just stay locked up indefinitely (forcing them to come to some settlement if they ever want to see the BTC again). After some lengthy period of time (say 1 year), the funds could simply revert to the operator of the escrow service (to avoid having BTC in a limbo state permanently).
I believe there is an escrow service called ClearCoin (https://clearcoin.appspot.com/
) that operates very closely to your description. If my memory serves me they do not attempt to resolve any disputes. i.e. If the buyer receives the item in good condition but never releases the funds the seller is out of luck and after a defined period of time the BTCs return to the buyer.