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But also the distros that are derived from it such as Dragonfly BSD and DesktopBSD. Though I guess it won't be a major effect initially obviously, these teams (once a final release is out) might be able to produce an easy system for even the end user to take advantage of.
Though I wonder what they would come up with to do with such a powerful file system. I'd imagine some type of backup system for starters. It could be very interesting to see where this could go with it. In the meantime, I'm hopeful for FreeBSD 7.