Let me tell an example, the (Linux) NTFS driver supports transparent compression. Today CPU's are very fast and the disk bandwidth is very slow compared. So doing bulk data transfers, the disk bandwidth is the bootleneck. Would you be faster using the filesystem's transparent compression? In theory yes, CPU can [de]compress when transfering data and you must also transfer less data. No main Linux fs supports this, hopefully Reiser4 will in the future ... (there was hope for e2compr as well for many years but it didn't work out after all).
ext2 have supported this for ages, check out chattr(1),lsattr(1)
This feature is reserved for about 8 years. But it never worked reliable. Google for the story. I wrote above the keyword (e2compr).
In what way are the compression features in NTFS different?
It works reliable since about 8 years. Something what none of the main Linux filesystem can do today (ext3, reiserfs, JFS, XFS).
Szaka