Taken from TheVerge:
The main advantages of the new file system include the ability for Windows 8 to detect all forms of disk corruption, data striping support for performance, and an allocate on write model known as copy-on-write. Microsoft has used copy-on-write (COW) concepts in its SQL Server products and Volume Shadow Copy Service previously, enabling quick snapshots of large data sets.
ReFS cannot be used on removable media, nor can it be used to boot an operating system — it's simply for storage right now. Microsoft says the new file system will only be introduced as part of Windows Server 8, but Windows 8 client will be able to access and read ReFS volumes until it's fully supported in client operating systems in the future.I wonder when will this filesystem be available on Linux kernel as well. In the past, Linux communities has managed to work with FAT32 and NTFS very well and they are now considered stable and mature enough to be used in production machines.
I believe Windows 8 will be a hot topic when it came out later. Not only they will use new filesystems, new design, but also new controversial policy of UEFI which will force vendors to lock their product to Windows product only, disabling users to install another operating system.