Microsoft's ground-up database-driven filesystem, WinFS, was originally slated to be released as the default filesystem for Vista (formerly longhorn). That was canned, as development of WinFS was taking much longer than expected. But now it seems it may be finished much sooner than Microsoft expected, and a beta of the filesystem has been released, though not to the public.
Microsoft claims they will support WinFS in Windows XP and 2003 Server, and there are rumors of it being back ported to older versions of Windows as well. Despite its flaws, NTFS is a robust file system that was vastly superior to FAT32 upon its release. Perhaps WinFS will bring just as much improvement as NTFS becomes outmoded.