The iPad provides the ability to connect an SD card, which fulfils a similar use case... but discounting the iPad, OSX Lion takes steps away from the filesystem

The iPad provides the ability to connect an SD card, which fulfils a similar use case... but discounting the iPad, OSX Lion takes steps away from the filesystem, with all the files openable by a given application visible a la coverflow with a flick of the wrist. It also does away with the saving metaphor in many apps, further distancing the user from filesystem concerns. In light of this, it would seem more a matter of will than being "too hard" or "pie in the sky".