The file system is dead. Long live the File system.
We live in an interesting time. There are two technologies that aim to accomplish two very goals. On the one hand we have things like Amazon's S3, Hadoop, NoSQL, and a host of technologies that destroy the file system metaphor as we know it today. The future, if you believe it, lays in storing all data in some sort of distributed key/value store-based system. And then, on the other hand we have things like "FUSE" that attempt to translate various kinds of interfaces and data systems onto the file system metaphor.
Ok, so the truth is that the opposition between the "lets replace file systems" with non-file based data stores folks and the "lets use the file system as a metaphor for everything," is totally contrived. How data is stored and how we interact with data are very different (and not always connected) problems.
Let's lay down some principals:
There are (probably) more tools to interact with, organize, manage, and manipulate files and file system objects than there are for any other data storage system in contemporary technology.
Most users of computers have some understanding of file systems and how they work, though clearly there are a great diversity of degrees here.
In nearly every case, only one system can have access to a given file system at a time. In these days of such massive parallel computing, the size of computer networks, (and the associated latency) this has become a rather substantial limitation.
From the average end user's perspective, it's probably the case that file systems provide too much flexibility, and can easily become disorganized.
There are all sorts of possible problems regarding consistency, backups, and data corruption that all data storage systems must address, but that present larger problems as file systems need to scale to handle bigger sets of data, more users, and attach to systems that are more geographically disparate.
Given these presumptions, my personal biases and outlook, and a bit of extrapolation here's a basic feature set for "information storage system." These features will transcend the storage engine/interface boundary a bit. You've been warned.
Multiple people and systems need to be able to access and edit the same objects concurrently.
Existing tools need to be able to work in some capacity. Perhaps using FUSE-like systems. File managers, mv, ls, and cp should just work, etc.
There ought to be some sort of off-network capability so that a user can loose a network connection without loosing access to his or her data.
Search indexing and capabilities should be baked into the lowest levels of the system so that people can easily find information.
There ought to be some sort of user facing meta-data system which can affect not just sort order, but also attach to actions, to create notifications, or manipulate the data for easier use.
Now all we need to do is figure some way to build it.