+ - The default --delete algorithm is now --delete-during when talking to a
+ 3.x rsync. This is a faster scan than using --delete-before (which is
+ the default when talking to older rsync versions), and is compatible
+ with the new incremental recursion mode.
+
+ - Added the --delete-delay option, which is a more efficient way to
+ delete files at the end of the transfer without needing a separate
+ delete pass.
+
+ - You may specify --max-delete=0 to a 3.0.0 client as long as the
+ receiving side is at least version 3.0.0. This means that you
+ can pull from an older rsync with this option, but pushing to an
+ older rsync will generate an error. *Be sure to never specify a 0
+ value to an older rsync client, or it will be silently ignored.*