Dropbox, on the other hand, was designed around files, both from a UI point of view and an API point of view. This means their file syncing is very, very good. If a file gets put into a Dropbox somewhere, it ends up everywhere quickly, basically with absolute reliability… If you’re building an app that needs to sync, that kind of reliability is exactly what you’re looking for… Apps can build better UI on those files whether they’re stored locally, stored in Dropbox, or stored in iCloud. But Dropbox has proven it’s reliability, and iCloud hasn’t.

So while there is an argument to be made that Dropbox’s UI is a relic, its value as a syncing engine is still huge, precisely because it’s built around the paradigm of files, a paradigm we have decades of experience working with.

Steve Streza, Files as UI vs API

As much as iCloud is the right idea still not realized, Dropbox is the wrong thing done brilliantly well. And at the end of the day, that still amounts to the wrong thing.

Those of us used to, and clinging to, traditional file systems love it, and will continue to love it as it becomes marginalized into obsolescence, as the growing mainstream — those who aren’t power users but are increasingly empowered users, and who won’t get it and shouldn’t be subjected to it — sweep past it and into newer, better things.

iCloud could be that better thing, if Apple can nail it. Big if. So could something else, including a new version of Dropbox. But nothing and no one is there yet. So, as iPhones and iPads and other appliances bring computing to a broader user base than ever before, the services that bind them remain stuck between the best-ever version of the past, and a still sputtering and stammering future.