Today, the ZFS repository on MacOSforge was closed , likely meaning the end of Apple’s pursuit of Sun’s next generation file storage system for use in Mac and Macintosh OSX Server.? They also mention that the mailing list and repository are also being removed. As John Gruber points out , the writing has been on the wall for awhile as 10.6 betas had some support for the file system but the final releases (Client and Server) had it wiped from existence

Original post:
Apple no longer pursuing ZFS as the next generation file system for OS X