The following 2 screencasts demonstrate a basic napp-it install on OpenIndiana and the setup of netatalk version 3.0 for use with OSX Time Machine backups. Version 3 is very fast and I have tested from OSX: Snow Leopard, lion and Mountain Lion and have managed to almost saturate a Gigabit link to the ZFS storage appliance via AFP.
AFP in my opinion should be your preferred transfer mechanism if you are using Apple Macs and is much faster than standard SMB.
napp-it is a simply amazing project and really unlocks the power of ZFS and makes management of ZFS easy and accessible for anyone wanting to have their data sitting on reliable storage. Napp-it is feature complete and I highly recommend you try it out and if you like it, please consider making a donation towards its continued development.
This may also work on the newly released OmniOS which is a more server centric distribution also using the illumos core. This is probably better as a base for a ZFS storage appliance as it is targeted specifically for server only use cases and not a generic Desktop or server OS like OpenIndiana is. If anyone manages to get Napp-it to install on OmniOS please let me know so we can write up some napp-it specific instructions for others to follow.
Screenshot: Transferring a file via afp to napp-it
Screencast 1: Installing napp-it on Openindiana 1.51a5
Screencast 2: Installing netatalk version 3 on napp-it