-rsync 1.6.4 changed the behavior of --delete to make it less
-dangerous. rsync now only scans directories on the receiving side
-that are explicitly transferred from the sending side. Only files in
-these directories are deleted.
-
-Still, it is probably easy to get burnt with this option. The moral
-of the story is to use the -n option until you get used to the
-behavior of --delete.
+This option can be dangerous if used incorrectly! It is a very good idea
+to run first using the dry run option (-n) to see what files would be
+deleted to make sure important files aren't listed.