The OS file system has a limited future. This will not be a new idea to anyone accustom to using an iPad. A novice computer user can pick up an iOS device open an app, save a new document and easily open it again later. There's no need to remember where it was saved. The file system is abstracted away from the user and the app is their view into their documents. There is a sense of comfort and forgiveness. There's no fear that you may forget where you saved your document. In many cases there isn't even a "save" function. You just create and edit.
Sophisticated software * should * remove mindless obligations from the user. I for one am looking forward to the loss of directories and file types. Imagine a day when applications simply support all files. Open a text based document in a sketching app to draw new content. Or open it in a audio editor to add an audio track. That will be the end of the file system.
Here's some other computing obituaries to keep a look out for:
RAM size Disk size Passwords Input devices Connectors and cables