Update: ZFS will be in Leopard--sort of
InformationWeek is reporting that contrary to prior reports, a version of ZFS will be included in Mac OS X 10.5, Leopard.
Brian Croll, senior director of Mac OS X product marketing, previously said that ZFS is "not happening" for Leopard. Now Croll is clarifying what he meant by "not happening":
"ZFS is not the default file system for Leopard. We are exploring it as a file system option for high-end storage systems with really large storage. As a result, we have included ZFS -- a read-only copy of ZFS -- in Leopard," InformationWeek reported.
At some point Mac systems will read ZFS volumes, but not write data into ZFS until an even later data. You have to wonder what all of the secrecy and nuance is about. Sun CEO Jonathan Schwartz announced that ZFS would become the default file system for Mac OS X earlier this week.
That doesn't appear to be the case, at least for the near term, and Apple is not offering much of an endorsement for ZFS. The InformationWeek news story suggests that Leopard's RAID-Z system uses some aspect of ZFS to prevent data loss when a system loses power or crashes.
I am still waiting to hear back from Sun on this file system mystery....