[timburks]

Does the computer you are using have a hierarchical file system?

[chris24]

Of course, but would you really want to use a more advanced menu just to find a single-serving app on a mobile device?

[timburks]

I'd just let the market decide. With so many identical-looking screens of apps, most iPhones already are getting cluttered. I expect that we'll soon see a better (hierarchical) Springboard.