In Solaris 10, you may or may not have been taking advantage of zones on ZFS, and thus, zone cloning.
In Solaris 11, since you must give each zone its own ZFS subfilesystem, you may as well take advantage of cloning if you plan on creating more than one zone. This is particularly relevant given that, by default, all zones are created with the same small set of packages, but it can still take quite a while to initialize. In contrast, when using zoneadm -z newzone clone oldzone, installing a new zone takes only 10 to 15 seconds.
Tip
The one drawback of using the zoneadm clone is that you cannot clone a currently running zone. However, if you plan ahead and create your first running zone from a non-running template zone, you will take up no extra disk space and will also have a template immediately available for your next zone.
If you use cloning to create a zone, the new ZFS root filesystem will initially be a writable ZFS clone of the old zone filesystem, presuming...