Posted on wrong thread. Moved comment to https://steempeak.com/steem/@dhimmel/re-blocktrades-q7ba8r. Original below:

Are Steem / Hive transactions susceptible to replay (or do transactions encode some chain-specific information)?

If so, I'm assuming replay protection will be added to the fork? I could imagine some situations where users would want to broadcast to both chains (i.e. cross-posting), but wouldn't want to see accidental sending of both tokens.