Problems that are identified by Windows Server 8 on volumes protected with these features can be automatically repaired without bringing the disk or volume offline in most cases, and in many cases without any administrative intervention, either.
ReFS is also built to scale further than NTFS as well, an important point in the age of Big Data and private cloud operations. According to Microsoft, ReFS is designed to support volume sizes up to 2^78 bytes -- or 256 zettabytes -- using 16KB cluster sizes, while Windows stack addressing allows 2^64 bytes or 16 exabytes.
The point here is that ReFS scales to all practically known storage sizes and then same. (For example, Seagate sold a total of 330 exabytes of hard disk space in 2011.)
ReFS will be available only in Windows Server 8, not in the Windows 8 Consumer Preview or in the final release of Windows 8 on the client side.
Drawing a conclusion
At the time of the first technical preview of Windows Server 8 back in September 2011, I was very optimistic. The capabilities that were slated for inclusion in the release were outstanding and really changed the game for Windows administrators.
With this beta, a lot of that potential now is in the box and working -- with some warts, as you'd expect from beta software. All of that will get worked out as the teams work together toward final release.
Overall, though, I'm kind of surprised at some of the design decisions that have gone into the user experience for this server OS. Specifically, I don't agree at all with the Metro UI being default with Windows Server 8. It's a great design language and it enables some really useful scenarios for managing via the standard administration tools like Server Manager, but as a desktop metaphor, I think it's not useful to change the paradigm so many server admins expect.
In many places, the OS feels like a mixture of Windows 7 , Windows Server 2008 R2 and some Windows 8 Metro preview bits, and it just doesn't feel cohesive.
To my mind, it doesn't add value. In many places, the OS feels like a mixture of Windows 7, Windows Server 2008 R2 and some Windows 8 Metro preview bits. It doesn't feel cohesive, and on quite a few screens in particular, it's just plain ugly.