Peter Todd again. I don't like this.
Yesterday F2Pool, currently the largest pool with 21% of the hashing power, enabled full replace-by-fee (RBF) support after discussions with me. This means that transactions that F2Pool has will be replaced if a conflicting transaction pays a higher fee. There are no requirements for the replacement transaction to pay addresses that were paid by the previous transaction.
http://www.mail-archive.com/bitcoin-development@lists.sourceforge.net/msg08422.htmlThis means you can double-spend within a 0-confirmation against a recipient listening on the P2P network, just by sending another transaction with a higher transaction fee?
What is the motivation for such a change?