The upcoming FreeNAS version 8.3.1 will include encryption for ZFS file systems as the most important new feature. Currently, FreeNAS 8.3.1 is in its first BETA version, so it is not recommended to entrust any important data to this version - no matter if encryption is used or not. Besides encryption, there are also updates for iSCSI targets and Samba, which have not been tested yet, too, and are only available in a BETA version.
The plugins, on the other hand, should not change, popular functions like minidlna will hopefully also work smoothly with the upcoming version, after some minor problems with FreeNAS 8.3.0, which are a thing of the past with the current FreeNAS 8.3.0-p1. In general it seems to be recommended to always wait for a patch release and not to update directly to a new version. Users who like to experiment can Download FreeNAS 8.3.1-BETA 1 from the project website.