ZFS in Solaris 11 has had some powerful enhancements added to what was already a first-class enterprise filesystem. Multiple NAS vendors are now basing their offerings around ZFS.
On top of an amazingly robust filesystem, the serviceability integration given to OS upgrades and patching make it an outstanding base for the Solaris OS to run on. Even if you do not plan on making use of all the available features right away, it's almost a certainty that you will have an opportunity to use many of them in the future.
Tip
Crucial Tip for adding features to an existing/older ZFS pool
If you are importing a ZFS pool from an older version of Solaris, you may not be able to use the newer features right away. Remember that you need to upgrade the ZFS pool and filesystem versions via zpool upgrade, and zfs upgrade respectively. Remember also that these operations are non-reversible, and that ZFS filesystem version upgrades can have an impact on production during the time period the upgrade is...