When we launch Spoutible.com, you will be able to delete replies to your spouts. You won't have to endure abusive replies while you wait for a moderator.

When you block an account, you will also have the option to delete the account's recent replies to your spouts...

Also, when you block an account, they will not be able to add your handle to their spout, and they will not be able to reply to people who are replying to your spouts.