Awhile ago, there were rumors of Leopard getting Sun's clean-sheet designed file system from the future, ZFS. OS X server is getting it in Snow Leopard, according to Apple's preview page. The consumer version doesn't look to be receiving the theoretically incorruptible file sytem yet, but we can hope it'll trickle down eventually. [Apple via ZDNet]
First, there were rumors that ZFS was going to be included in Leopard and Microsoft has some rumors on a new file system for Vista. Last I checked, neither happened.
That said, if Apple can get ZFS operating, it will effectively leap-frog Microsoft's own file system efforts. While it would be especially impressive to have this at the consumer-level, just having it at the server-level would be a huge leg-up on the Redmond elves.