dirtyrat: You're right, there is a lot of infrastructure work to be done. As I've said before, it would be a much easier problem to solve if there weren't any legacy compatibility issues. We could build metadata right into all the filesystems and protocols and/or file formats. Then all that would need to be done would be to develop the features that take advantage of the extra information. It then quickly becomes more of a straight HCI issue. But as it stands now, it is a pretty massive engineering problem, a computer science problem, and a HCI problem. Not simple. ;-) It is really foundational, which is a curse and a blessing. The curse is of course that it takes a lot of work to graft this onto existing infrastructure. The blessing is that once it is there, there are all sorts of cool things that can be done relatively cheaply. Hopefully this (huge) benefit will get people inspired to work on the issues. We'll see how it goes.